The post Pick and Place appeared first on PIC Microcontroller.

After the simple interfacing of the PIC18F4550 microcontroller with the DS3231 RTC, now let’s add the alarms functionality and temperature monitor to our previous project.
Interfacing PIC18F4550 with DS3231 project link:
Real time clock & calendar with PIC18F4550 and DS3231
As written in the datasheet the DS3231 RTC has a built-in 2 alarm functions and a digital temperature sensor with an accuracy of ±3°C.
Hardware Required:

• PIC18F4550 microcontroller
• 20×4 LCD screen
• 10K ohm variable resistor
• 330 ohm resistor
• LED
• 3 x push button
• 5V supply source
• Breadboard
• Jumper wires

DS3231 board contains the following components:

• DS3231 RTC – datasheet
• 3 x 4.7K ohm resistors
• 0.1uF ceramic capacitor
• 3V coin cell battery

The circuit:
Project circuit diagram is shown below.

To simplify the circuit, I used the DS3231 board, this board basically contains the main chip which is the DS3231, pull-up resistors (4.7K) of SCL, SDA and INT/SQW lines and coin cell battery holder. There is also 24C32 EEPROM and some other resistors (not used in this project).
The DS3231 board is supplied with 5V as the microcontroller and the 2004 LCD, there are 3 data lined connected between this board and the PIC18F4550 MCU, SCL line is connected to pin RB1, SDA is connected to pin RB0 and INT line is connected to pin RB2 which is the external interrupt 2 pin of the PIC18F4550 MCU. The DS3231 interrupts the microcontroller when there is an alarm.

In the circuit there are 3 push buttons: B1, B2 and B3. These buttons are used to set time, calendar and alarms. Time and calendar can be adjusted with B1 and B2, button B1 selects time or date parameter (time parameters: hours and minutes; calendar parameters: day, date, month and year) and B2 increments the selected parameter. The button B3 and B2 adjust alarm1 and alarm2 parameters (hours, minutes and ON/OFF), button B3 selects the parameter and B2 increments the selected parameter.
There is an LED connected to pin RB6, this LED is used as an alarm indicator (alarm1 or alarm2), so if there is an alarm the DS3231 pulls down the INT pin which interrupts the microcontroller and the microcontroller turns the LED ON, here button B2 turns both the LED and the occurred alarm OFF.
In this project the PIC18F4550 MCU uses its internal oscillator and MCLR pin function is disabled.
CCS C code:
The C code below was tested with CCS C compiler version 5.051.
By reading the datasheet of the DS3231 RTC the code will be more easier!
The hardware I2C module of the MCU is initialized and configured using the following CCS C function with a speed of 100KHz:
#use I2C(master, I2C1, FAST = 100000)

I2C1: use first I2C module.
The DS3231 works with BCD format only (except temperature) and to convert the BCD to decimal and vise versa I used the following functions (example for minute variable):
minute = (minute >> 4) * 10 + (minute & 0x0F);                                  // Convert BCD to decimal
minute = ((minute / 10) << 4) + (minute % 10);                                   // Convert decimal to BCD
Code functions:
void DS3231_read() : this function reads time and calendar data from the DS3231 (seconds, minutes, hours, day, date, month and year).
void DS3231_display() : displays time and calendar data, before displaying time and calendar data are converted from BCD format to decimal format. This function displays the calendar by calling a function named void calendar_display() .
void alarms_read_display() : basically this functions reads alarm1 and alarm2 minutes and hours. It also reads the DS3231 control register, status register and 2 temperature registers.
The other job of this function is to display alarms data (hours, minutes and status) and the temperature value. The alarm status are extracted from the control register.
int8 edit(parameter, x, y) : I used this function to edit time, calendar and alarm parameters except the day. I used a variable named i to distinguish between the parameters:
i = 0, 1 : time hours and minutes respectively
i = 2, 3, 4: date month, year respectively
i = 5, 6: alarms hours and minutes respectively
i = 7: alarms status (ON or OFF)
After the edit of time/calendar/alarms the data have to be converted back to BCD format and written to the DS3231.
for more detail:  Real time clock with 2 alarms and temperature sensing using PIC18F4550 and DS3231

The post Real time clock with 2 alarms and temperature sensing using PIC18F4550 and DS3231 appeared first on PIC Microcontroller.

Bosch Sensortec announces a world first in sensor technology: the BME280 Integrated Environmental Unit combines sensors for pressure, humidity and temperature in a single package. This unique sensor has been developed to support a broad range of emerging high performance applications such as indoor navigation, home automation control, personalized weather stations and innovative sport and fitness applications. The precise altitude measurement function of the BME280 is a key requirement in applications such as indoor navigation with floor tracking where exceptional accuracy, low temperature drift and high resolution are needed. Additionally, the BME280 has a best-in-class response time of just one second for humidity determination, excellent ambient temperature measurement and low energy consumption.

More precise measurement at lowest power consumption

With a small footprint of just 2.5 x 2.5 mm²and a height of 0.93 mm in a space-saving 8-pin LGA package, the sensor offers high design flexibility and is ideally suited for mobile devices with limited space such as smartphones, tablets, smart watches and electronic wristbands. Very low current consumption of only 3.6 µA (at 1 Hz) makes the BME280 Integrated Environmental Unit particularly suitable for battery-driven applications. Three power modes and separately configurable oversampling rates for pressure and temperature measurements allow designers to adapt the BME280 to a wide range of use cases.

The humidity sensor within the Integrated Environmental Unit measures relative humidity (0% to 100%) across a wide temperature range from -40°C to +85°C with a fast response time of less than 1 second. The humidity measurement accuracy is ±3% with a hysteresis of 2% or better, and the temperature reading accuracy is within 0.5°C.

Read More: BOSCH BME280 SENSOR COMBINES PRESSURE, HUMIDITY AND TEMPERATURE MEASUREMENT

The post BOSCH BME280 SENSOR COMBINES PRESSURE, HUMIDITY AND TEMPERATURE MEASUREMENT appeared first on PIC Microcontroller.

Under the “Power by Linear” branding it recently created for the product lines it acquired with its purchase of Linear Technology, Analog Devices has added the LT3964, a dual channel, 36V, high efficiency, synchronous, step-down LED driver with internal 40V, 1.6A power switches and an I2C interface that simplifies LED dimming control.

The post 36V, 2-ch, 1.6A synchronous buck LED driver has I²C dimming appeared first on PIC Microcontroller.

Researchers at EPFL in Switzerland have found that adding large organic compounds called guanidinium (CH6N3+) into methylammonium lead iodide perovskite solar cells can provide stable power efficiency of 19%, approaching that of silicon cells.

The post Perovskite solar cells stabilised at 19% efficiency appeared first on PIC Microcontroller.

Theory of operation

In series thermocouple soldering iron have a thermocouple in series with their heating element and thus only have two connections (actually one more which is electrically connected to the tip for ESD purposes). When a voltage is applied to the two terminals the tip heats, when unpowered the thermocouple voltage can be read.

This controller uses a skipped variable puls modulation to keep the temperature of the tip steady. During the off period the thermocouple voltage is sampled and the temperature is calculated from that. The temperature is then compared to the setpoint and pulses are skipped when the temperature of the tip is higher to allow  it to cool down. If the temperature of the tip is less a pulse is applied. When the temperature is near (approx. 5-10 degrees C) its setpoint shorter pulses are used to minimized the overshoot.

Connections

A powersupply capable of supplying 12-24VDC, 3A is needed to power the soldering iron controller. For maximum performance 24V, 3A is required. Connect the positive side of the powersupply to the +24V and the negative side to the -24V terminal. To use the ESD features connect EARTH to protective earth. The tip is grounded through this connection with a 1MΩ resistor.

The + and – connections from the soldering tip are connected to the T12+ and T12- terminals. If you got the handle officially red is positive, black negative and green tip. If the tip is connected backwards, the temperature display always states the tip is at 25 degrees C but it gets really hot. Please disconnect the power immediately and rewire the handle!!

When a solderinghandle is connected !TP and GND should be shorted too (all the magic should be handled in the solderinghandle connector). Optional there is a powerdown pin (!PD) which can be used to detect when the handle is placed in a holder. The temperature is set to 150 degrees when this pin is grounded. An optional 3V3 pin is available for powering your fancy handle detector.

Read more: 70W soldering iron controller

The post 70W soldering iron controller appeared first on PIC Microcontroller.

Abstract:

This report represents the design and implementation of a skin temperature measurement system. The system aims to measure the skin temperature from a sensor and send it to the PC using a USB cable to display on screen. The data needs to be updated every second.
The PIC18F4550 microcontroller has been used in this project to obtain data from the sensor and send it to the PC using USB 2.0 that has been built into the microcontroller. The microcontroller has a 10-bit Analog Digital Converting accuracy that is one of the important criteria for this design as it is going to be used for medical purposes. As the project concentrates more on designing software than hardware, the EasyPIC4 development board was used which comes with all hardware required for this project. The Michel Jackson diagram method was used to design and implement the coding program for the microcontroller software part of the system. The MikroC IDE has been used to compile and load the program into PIC18F4550 microcontroller. The program for the microcontroller uses C language that aims to keep the USB link alive by using interrupt function. A sensor collects data from sensor as 4 bits and send it to the PC every second using a USB cable.
The data received from sensor, will be sent by microcontroller to the PC. The Visual Basic software was used in the PC side of device to catch and output the data on the screen. A template file for the Visual Basic program was generated by Easy HID wizard to make software programming part easier for designer. The template file was modified in such way that can operate following activities for a user purpose:  A message that indicates if USB connector is plugged or unplugged from the PC.  Different techniques to display data on screen (textbox & progress bar). Button control key to end and exit from program.  Finally labeling the Form as well as display and control for user attention. The USBTrace analyzer has been used in the scenario any problems occur during or after the design and construction of the software. The software enables a user to monitor the data on the USB bus that sends the data to the PC from microcontroller.

Introduction:

There are different techniques used to send a data from a sensor to a PC for further operation and outputting results. A requirement of the project is that the customer needs an easy to use serial cable for transferring the data from a skin temperature sensor to the host computer.
Any data communication from peripheral device to a host computer by a cable can be divided into two main groups serial and parallel data transfer. In a parallel communication, group of data will transfer simultaneously on more than one communication lines while in a serial communication the data transfers one bit at a time on single communication line. This means the ability of data transferring at each given time in the parallel communication is greater than the serial communication which makes the device faster.
There are a number of advantages of using a serial port over a parallel port such as:
The serial ports are smaller as they have a single line to transfer therefore fewer pins compare with the parallel port needed.
Less EMI and interference compare with the parallel port which has many wires switching over each other all the time.
Less time for error correction compare with the parallel ports that have many lines to transfer the synchronized data.
Finally the serial port is easy to connect compare with parallel port.
Universal Serial Bus (USB) is an external serial interface to transfer data from one electronics device to another using a USB cable. The USB is a set of connectivity specification was developed early 1996 by Intel to establish communication between a peripheral device and a host computer which uses a serial stream. The USB cable provides a high speed, easy connectivity and automatic configuration when it is plug in. The first USB specification was developed was a USB 1.1 that had up to 12Mbps data transfer rate. However in April 2000 the USB 2.0specification was released that had speed of up to 480Mbps which was 40 times greater than the USB 1.1.

In this project the USB 2.0 has been used to transfer data from the peripheral devices (temperature sensor device) to the host computer by USB cable.
There are a number of advantages that make companies to design their product to use the USB 2.0 instead of a serial or parallel port, more details of the USB 2.0 and some of its advantages are mentioned in following: Easy to use for the user as it has a plug and play function that means the user can connect any device to the PC without rebooting the system. Fast enough to avoid a communication bottleneck, latest standard by up to 480Mbit/sec data transfer rate. A standard PCs comes with 2 or 4 USB ports fit in, it will enable a user to connect up to 127 devices to the PC using the USB hubs. The size of a USB port is quit smaller and it is easy to connect compared to other types. Using the USB 2.0 gives more control to the user to control the device using its PC as it has two ways communication. Low cost and power consumption from the PC.
Is it not sounding old? The answer is obviously „yes‟. Technology is always progressing. It pays to move forward with new technology than try to employ the old or current. However USB 2.0 technology is widely popular and has become a standard requirement in PCs hence will be around for some time to come.
In this report convenient and up-to-date techniques and technology have been used in order to use the USB 2.0 cable for the system that enable the user to achieve their goal to satisfy their customer. After some research over the technologies that are available in the market to convert an input data to 10 bit digital data and the chips that uses USB 2.0 technology to respond to different events on the bus, various chips were found that required a range of firmware support in order to establish USB communication.

The PIC18F4550 microcontroller was chosen to be suitable solution for this project as it satisfies the specification as it has both technologies required for this project built in (10bit A/D conversion, USB2.0) as well as providing more flexibility, reliability and future modification to the design.

2)  Aim and Objectives:

2.1. Aim:

The aim of this project is to design a system that can measure skin temperature by an analog temperature sensor and screen out the result on a PC‟s screen every second.

2.2. Objectives:

Objectives for the system can be broken down to the following objective: 1. The primary objective of this project is to use a serial data transfer cable. 2. Secondary objective is to have good data accuracy for the system. 3. Third obj

ective is to make more flexibility and compatibility for the system for future modification. 4. Final objective is to use an easy to understand and up to date technique to output the data on screen.

2.3. Specification:

1. Using the serial data transfer techniques (USB 2.0 Technology) as the customer wants it to use as an On-The-Go device. 2. Accuracy of minimum 8-bit to convert an analog input signal to corresponding digital number. A

s the device designed to be use for medical purposes to diagnose the skin diseases. 3. Updating the reading data from the sensor every one second. It is more accurate to get average from token results as the reading is not stable. 4. Display the input data on the screen. Use simple and easy to use technique to display the data for the user.

2.4. Deliverable:

The project outcome will be as follows: A working model of the Skin Temperature Measurement system. (Hardware) The software required to produce the behaviors specified. (Software) Research for upgrades and add-ons for the system i.e. software and hardware. Interim and final project documentation. Software and hardware testing.

3) Technical background and context (hardware/software):

3.1. Hardware:

1) Easypic4 Development Board 2) PIC18F4550

3.2. Software:

1) MikroC Compiler for PIC 2) PICFlash2.0 with mikroICD 3) USBTrace USB protocol analyzer 4) Microsoft Visual Basic 6.0 5) Easy HID USB wizard

4) Technical Approach:

The first plan of action was to study the customer‟s requirements, specifications and to identify key factors of the project. The next step was to obtain information from journals and the Internet to acquire information on how existing systems with serial ports work and to investigate what current technologies are in place that gather data from skin temperature sensors and communicate in similar fashion with a PC using USB technology.
After enough research on technologies available, the following hardware & software parts have been chosen, that are suitable for the project in order to meet the required specification set at the start of project which satisfies the criteria:

1. Hardware:

The hardware component of the project can break down to two main components:

1.1-PIC18F4550 Microcontroller:

The PIC18F4550 Microcontroller has the following features: The main feature of this microcontroller is that it has built in the USB 2.0 interface.  Low power consumption (nano Watt Technology)  Enhance Flash program and large amount of RAM memory for buffering (1Kbyte Dual Access RAM for USB)  Has different pin layout (40 and 44 pins) High Performance and speed up to 12Mb/s in Full speed mode and 1.5Mb/s in low speed mode. Accuracy of 10-bit to convert analog signal to digital number relatively. Up to 13 analog to digital converter model channels with programmable accusation time.

The project uses the 40 pins chip shown in figure(1) as it was compatible with development board provided by university lab (EasyPIC4) that has all features that satisfy the project needs.

In this part of the report more details of some features and functions of PIC18F4550 that will be needed to use later on for the project will be given in following:

USB Bus Interface:

The microcontroller supports USB interface to communicate with a host computer directly. It can transfer data with a full speed (12Mb/s) or low speed (1.5Mb/s) that allows fast communication between the device and a PC.
Figure (2) shows the infrastructure of the USB section of PIC18F4550 that use Pin23 (RC4) and Pin24 (RC5) for USB interface. RC4 is used to indicate the D- data pin and RC5 uses to indicate the D+ data pin. These pins are connected internally to two pull up resistors that can select full speed operation by connecting the resistor to the D+ data pin and low speed by simply connecting the resistor to the D- data pin.

The register UPUEN is use internally to activate and deactivate the pull up resistors. For disabling resistors simply configure UPUEN= 0x00 and vice versa to enable them the UPUEN register has to be assigned to 0xff. These resistors can be connected externally as shown in figure but in the case of the external resistors, they can be disabled and enabled manually by connecting the resistors to 3.3 volts supply, but the user has to make sure to disable the internal resistors in the scenario of where the external resistors are to be used.
Three control registers are managing operation of the USB interface internally and 22 register are being use to manage the actual USB transaction. But MikroC language has a USB library function that can be used in order to implement the USB transaction. However there is no need to configure these registers in this project.

10bit analog to digital converter module:

The analog to digital converter module has 13 Input/output pins for the microcontroller with 40 pins that has been used for the project as it was mentioned before these pins provide up to 10-bit analog signal to digital number accuracy. The module has five registers:  A/D Result High Register (ADRESH)  A/D Result Low Register (ADRESL)  A/D Control Register 0 (ADCON0): To control operation of analog to digital module.  A/D Control Register 1 (ADCON1): To control function of port pins.

A/D Control Register 2 (ADCON2): To configure the A/D clock source, programmed accusation time and justification. Figure (3) shows the actual register configuration in order to operate in such way which can take analog signal from channel0. In Figure (3) the ADCON0 was assigned to zero to select channel 0 as an analog input.

In Figure (4) the ADCON1 register was assigned to zero to set all channels to analog.

In Figure (5) the ADCON2 was assigned to 0xA6 to set the Ref=+5Vand A/D clock = Fosc/64, 8TAD in this project.

Input/ output ports:

There are up to five ports (PORTA, B, C, D, E) are available for the PIC18F4550 microcontroller. Each port can be used as an either input or output for other peripheral features on the device. Each port has three registers to control operation which has to initialize and activated before it can be use. The following shows the operation of these port‟s registers:
TRIS register is use to specify direction of data.  PORT register that reads the pin level of device. LAT register that latch the output or read and modify and write operations on the value of I/O pin.
It is better to select the PORTA as an analog input as several of its pins multiplexed with an analog inputs. PORTA is an 8-bit wide and bidirectional. To set PORTA as an input pins, the TRISA has to be set to 1. PORTB is an 8-bit wide and bidirectional which is going to be use as an output port by setting TRISB to 0.

Interrupts:

In general interrupt is a signal that indicates attention or change in execution in programming. In this case the processor saves its states and check interrupt vector address that give the address of Interrupt Service Routine (ISR), at this point the processor will execute the ISR where the instruction for this interrupt has been stored. After the processor finishes executing of the ISR instructions, it will go back to the main program and continue from where it is left of by checking its state. The PIC18F4550 microcontroller has two interrupt sources and a priority feature that allow each of the interrupt sources to get assigned to high priority that is located in 000008 interrupt vectors and low priority that is located in 000018 interrupt vectors.
From the name of priority can recognize that each high priority interrupt should be able to interrupt the low priority interrupt which is in the progress.

The 10 registers used to control interrupt operation has been listed as follows:  RCON  INTCON INTCON2  INTCON3  PIR1, PIR2  PIE1, PIE2  IPR1, IPR2 However there is no need to set all register for any interrupt operation. Three bits are controlling interrupt source operation: 1. Flag bit: This bit is indicated when interrupt events have occurred. 2. Enable bit: This bit allows the program that is being executing to link to the vector address in the case of flag bit is set. 3. Priority bit: This bit use to select a high priority from a low priority.
As the project contains of the interrupt operation to keep the USB function alive, there is no need to set some of the registers as well as the interrupt bits. And Timer0 function will be use as an overflow function to produce the 0.832ms delay we need before sending the keep “alive” messages.
In this part there is a need to set the registers that we need in order to disable and enable interrupt function. Before any interrupt operation is to be used it is better to disable all the interrupts in the system and this can be done by setting the Figure (6) register:

By setting INTCON = 0X00 we can disable all the interrupts as shown in Figure (6). The next step is to set INTCON2 = 0xF5 that set Time0 overflow and RB port as high priority and disable all the PORTB pull ups and set all the interrupt on the rising edge.
After that the INTCON3 has to be set to 0xC0 that enable the interrupt and set it as a high priority. The rest of register can be set to zero as they disable the functions.
Finally the interrupt has to be enabled where it will be used, this will be done simply by setting INTCON register to 0xE0 that enable the Timer0 overflow interrupt and all the high priority interrupts as shown in figure above.

Timer0:

Timer0 can be using as either a timer or a counter in this project it has been used timer0 as an interrupt overflow, it is incremented on every clock by default. Here the timer0 will be used to re-enabling the USB function every 0.832ms, this achieved by setting the following register to the calculated prescale value shown in following: The timer0 can be set to the 256 pre-scale values and the 8 bit mode. However crystal frequency is 8MHz but the CPU is set to operate in 48MHz clock this setting will be described later. Selecting timer value of 100 (TMR0L=100) with clock frequency of 48MHz gives the timer interrupt interval of 0.832ms that calculated below: T=1/f → T=1/48M=0.02083us (256-100)×256×0.02083us= 0.832ms The timer0 register T0CON uses to control the all aspect. After looking at the register instruction and previous knowledge of setting, the T0CON should be set to 0x47in order to enable the timer0 and set all the bits to what it needs to be as shown below.

Circuit Diagram:

After getting all this information about PIC18F4550, The actual hardware connection between the microcontroller and the host computer has been designed and shown in Figure (7).
The designed circuit diagram shows a sensor who is connected to channel0 (AN0) of the microcontroller. The USB cable is used to connect USB connector to the host computer. The USB connector connection was established by connecting D- to port pin RC4 and D+ to port pin RC5 of USB cable. The microcontroller clock is operating on 8MHz crystal and reference voltage was 0 – 5 volts.

1.2-EasyPIC4  Development Board:

EasyPIC Development board was designed and built by the MikroElectronica to use for the Microcontrollers with 40 pins layout. The board was recommended and provided with the university and it was familiar for me as it was used for other project previously.
The board has all the hardware features that needed for this project, therefore there is no need to design and build the hardware that leaves more time for designer to spend on the software part of the project.
In order to activate the hardware parts of development board that is needed for the project. The following setting and connectivity has to be established by the user. In this section more detail of the hardware parts of EasyPIC4 board and how to set the parts in order to operate as expected given in Figure (8):

The hardware components used in this project have been indicated in Figure (8) and their settings have been described in following:

Switches:

The board has two sets of switches (SW1&SW2) that have two positions (ON&OFF) which activate and deactivate the connection. First sets of switches (SW1) are used to enable connection between the microcontroller and the input ports as well as the external pull up/down resistors. In order to avoid effect on the input port voltage level these resistor should be disabled. In this project it is better to leave all the switches OFF as the analog input is going to be measured. The next sets of the switches (SW2) are used to enable the LEDs connected to the PORTs. In this project the PORTB is enabled by placing the switch in the ON position and leave the rest of the other ports in the OFF.

Power Supply:

The board can be powered up by either regulated power from the USB cable or by the external power supply. In the case of using regulated power from the USB programmer cable the power will be supply while the board connected to the PC bye the cable. In this case jumper JP1 should be set to the right hand position as shown in Figure (10):

USB 2.0 Programmer:

In order to use this port, the PICFlash2 programmer software which comes with the board or will be provided on the Microchip website which has to be downloaded and installed onto the PC. This software enables the user to load a program into microcontroller. There is no need to reset the microcontroller as programmer will reset it automatically. There is one jumper (JP5) located for this part that should be set as a default position.

MikroICD Real Time Hardware in Circuit Debugger:

MikroICD Debugger is a tool that enables the user for Real Time debugging on hardware. MikroICD programmer provides a service for the user to check the program variable values while the program running on the microcontroller using a Special Function Register (SFR) and EPPRAM. This tool can be used through MikroC compiler, it can communicate with the compiler and supports common debugger commands that shown in Figure (12).

LEDs:

Light Emitting Diodes (LEDs) will be used commonly on the board to display output. The board contains of the 36 LEDs of which 8 LEDs are used for each the PORTA, B, C, and D except PORTE that has 4 LEDs. In this project PORTB was selected as an output by changing the position of SW2 to ON position, and monitor output value all the time while the program was tested.

USB Communication:

This USB connector can communicate with those microcontrollers that have the USB technology built in such as the PIC18F4550 microcontroller. To enable communication between the microcontroller and connector the jumper set group has to set to the right position that disconnect the pins RC3, RC4 and RC5 from the rest of the system and connect it to the USB connector.

A/D Converter Input:

The board has two potentiometers built in which can work with an Analog Digital Converter (ADC) to produce the input range of 0 to 5 volts. These potentiometers can be used for testing purposes in the case of unknown sensor is going to be used.
In this project these potentiometers have been used as the customer did not provide any details of sensors that are going to be used as two analog signals were presented by these potentiometers in the same time.
To connect these two potentiometers the following connection has to be established. The jumpers group JP15 can enable connection between P1 and one of the following pins: RA0, RA1, RA2, RA3 and RA4. The jumper group JP16 can enable connection between P2 and one of following pins: RA1, RA2, RA3, RA4 and RA5. In this project the jumper JP15 has to be connected between P1 and pin RA0.

The corresponding switch (SW1) has to be in the OFF position that disconnect the Pull up/down resistor from PORTA of the circuit, this gives measurement result without any interference.

Direct Port Access:

There are five direct ports were provided on the board to enable the user to connect to any peripheral such as sensor in this case. Each groups of port pins are connected to one of the PORTs A, B, C, D and E which have 10 pins connecter VCC, GND and up to 8 port pins. The user has to make sure the connecter is disabled from on board peripheral by checking the jumper next to it before connection to the external peripheral has been established.

2. Software:

The software part of this project can be broken down into two different programs. The first program has been designed and implemented was the microcontroller program, and second program was the host computer program. By using the following techniques that enable the user to develop application for this embedded system.
The project consists of two software part as it is mention before in the report:
Microcontroller Software: This part consists of design and program the microcontroller that can take input data from channel0 (AN0) and use USB cable to send it to the PC each second for further operation and screen out.
PC Software: In this part the program has to be design and implement to detect any USB connection and catch data that was send from the microcontroller and screen out for the user.

2.1-Microcontroller Software:

The main part of this project is consists on the software design that should satisfy the customer requirement. The hard ware part that was described in the previous part of this report gives more information of the PIC18F4550 microcontroller and function‟s which can be used in this part of the project.
The software program for the microcontroller has to get the data from the sensor and send it to the PC using a USB cable. However this data has to be updated every second. The PC software part of project will be described later in this report which uses Visual Basic software to catch and output input data on screen.

Before we start to design the software program for the microcontroller, the operations that have to be done to satisfy the specification has been broken down into following Jackson Structure Programming (JSD) method:

2.1.1-JSD diagram:

The Jackson System Development (JSD) diagram is a liner method for software development that uses life cycle structure to produce final code for the microcontroller. Following JSD diagram designed for the microcontroller software part of the system using Microsoft Visio.

Diagram explained:

1) The first step in the diagram was initialization of the ports, variables, TIMER0 and interrupts.

2) Next, the main program is executed which is an iteration type of box that indicates an infinite loop (main loop). The loop is important because the microcontroller reboots if the end of the program is reached.

3) Generating interrupt to making the USB link alive during the operation of sending data to the PC. Enabling the interrupt and Timer0 has been described in the previous microcontroller part of this report.

4) The next step on the diagram is to enable the USB device on the chip that carries the data.

5) On the next step the data is read from the specific channel of the input port on the board and the read data was saved in the variable S.

6) In this step the data has been saved on the variable S has to be send to the PC using the USB cable.

7) Disabling the USB device is step to make sure there is no more data can be detected.

8) And finally 1 second software delay is produced in this part the program that makes this loop wait for one second before actually going into next loop.
Following JSD Diagram, the C program Code is written for microcontroller but before writing code it is best to understand the functionalities of the MikroC compiler that is going to be used in this project.
The reason MikroC has been chosen for the project was that as it has the HID library function built in as well as some operation such as the HID terminal can help us to interface the microcontroller with the PC to send and receive data.

2.1.2-MikroC Compiler for PIC:

MikroC is one of the rich feature development tools for the microcontrollers. It is provide the easiest solution without compromising the performance or control for developing embedded systems.

It provides a successful match featuring highly advanced IDE, ANSI compliant compiler, broad sets of hardware libraries, comprehensive documentation and plenty of ready to run examples.

In this part the software has been downloaded and executed by double clicks on MikroC icon on desktop which bring up the window where a new project can be created for this application.

Each application can contains of a single project file (name.ppc) and one or more source file (name.c). The compilation can be done on those file which are part of the project.
First step is to create a project that can be done easily by dropping down the menu and then project>new project which take us in another window that has following parts to fill up:

1. Project name: Each project has to have a name that can be chosen by the user in this project the name selected to be temperature.

2. Project path: this can be any location in c directory or anywhere else where the user wants it to save the file. In this project is selected as default that takes us to the Mkiroelectronika examples folder. C:\ProgramFiles\Mikroelektronika\mikroC\Examples\EasyPic4\extra_exampl es\HID-library\

3. Device: In this part the PIC to be used has to be selected. In this project PIC18F45550 was selected as it is going to be use on board.

4. Clock: This gives more capability to the user to select clocking user want to use on their project. In this project 48MHz was selected. The rest of device flag has to be selected by default. By clicking on save and then ok the software will create new project and empty source file that can be name by the user later.

In this file the C coding for microcontroller is written that operates as it has been explain by JSD Diagram method previously.
In this part before writing the code software for this project a brief description of some of the library functions such as the USB HID and the ADC used in this application is as follows:

i. ADC library function:

This library function can be used to read 10-bit unsigned data value from the specific channel. This value is saved into unsigned long variable for more operation. The prototype for this function is: Unsigned Adc_Read (char channel);

ii. USB HID library function:

MikroC has a library that enables the user to connect and work with the Human Interface Device (HID) via Universal Serial Bus (USB). The HID is a type of computer device that enable the user to interact and take input directly from other input humans (microcontroller input).
In the case of using the PIC18F4550 microcontroller or any other PIC that has USB device built in the following USB library function can be used:
HID_Enable: This function has been used to enable the USB communication that has to be called before any other function of this library and it does not return any data. The function has two arguments which have to be set before using them (read buffer address, write buffer address).

HID_Read: This function is used to get data from the USB bus and store received data into the read buffer. This function does not have any argument but it does

return the number of characters that has been stored in the receive buffer previously.

HID_Write: This function use to send data from the write buffer to the USB bus. The function does not return any data. To use this function has to be careful to copy the same buffer name that has been specified in the initialization and length of data that is going to be send has to be specified in the function argument.

HID_Disable: This function always use at the end of this library function and disable the USB communication. This function does not have any argument and returns no data. Any project that uses the USB library should include a descriptor source file that contains of a vendor ID and name, a product ID and name, a report length (input/output) and other relevant information. In MikroC this can be created directly by using the USB HID terminal tools.

Bring down the menu and then tool>HID terminal after clicking on the HID terminal, it will be open. On this window click on the descriptor that will go to next window. In this window fill up all the descriptor information as shown in Figure (17) and click on create button.

The vendor ID has been set to 1234 (equvalient to decimel 6460) and the Product ID to 1 which was provided by the USB-IF (www.usb.org) which is non-profit corporation that provides software and hardware to help developing and testing products.

By clicking on create button and selecting the project location the compiler will create the USBdsc.c descripter file that shown in appendix.

This file has to be added to the project with either using mikroC IDE tools or include to the project by using #include on the program file.
The program has to have the function to keeping alive the USB connection by sending message to the PC every few millisecond.

This can be achieved by setting up a interrupt that uses the Timer0 to over flow every 0.832ms and inside interrupt service routine the USB function HID_InterruptProc has to be called following that the Timer (TMR0L) is reloaded and the timer interrupts are reenabled just before returning from the interrupt service routine.

2.1.3-Microcontroller clock:

The PIC18F4550 microcontroller requires a 48MHz clock frequency for its USB module and the clock range of 0 to 48MHz is needed for the microcontroller‟s CPU. In this project the CPU clock has been set to 48MHz. this setting has been done using MikroC compiler.
The circuit is shown in Figure (18) illustrate the PIC18F4550 clock circuit. As it is shown in the circuit it consist of following components that has to be set in order to clock in the specific clock frequency:

A 1:1 – 1: 12 PLL prescaler and multiplexer

A 4:96MHz PLL

A 1:2 – 1:6 PLL postscaler

A 1:1 – 1:4 oscillators postscaler

As it has been mentioned before the crystal frequency is 8MHz. In order to set the microcontroller and the USB module operate with 48MHz clock, the following has to be selected in the Edit Project option of MikroC IDE:

The _PLL_DIV2_1L was selected that makes 8MHz clock is divided by 2 to produce 4MHz at the output of the PLL prescaler multiplexer. The output of the 4:96MHz PLL is 96MHz now. It needs further to be divided by 2 to give 48MHz at the input of multiplexer USBDIV.

The _USBDIV_2_1L has been selected to provide a 48MHz clock to USB module and 2 for the PLL postscaler.

The CPUDIV_OSC1_PLL2_1L has been selected to choose PLL as the clock source.

The _FOSC_HSPLL_HS_1H has been selected to choose a 48MHz clock for the CPU.

The CPU clock has been set to 48MHz using the Edit Project option of MikroC IDE.

Figure (19) shows the setting that has been done in the MikroC Edit Project option in order to select 48MHz clock frequency for the USB operation and the CPU clock.

The source code main program file for the microcontroller that shown in appendix 1 has been written base on the JSD Diagram and the information was provided in previous part of the report. More details of source code will be given in the following part of report.

2.1.4-Main Program for Microcontroller:

This program has been written to connect the PIC18F4550 microcontroller to the PC using a USB cable. One of main important aspect that should be taken into consideration when the USB link is going to be use in any embedded design is to make sure that the USB link is alive during any operation of the bus. The microcontroller is supposed to obtain the data from a temperature sensor that has been connected to the channel0 of the microcontroller. The data was obtained from the sensor is in Celsius and has to be sent to the PC every one second to get display on the screen.

The Visual Basic is used to display the sensor value on the screen that will be explained later in this report. The PIC18F4550 is operates from the 8MHz crystal however the CPU clock frequency and the USB module had set to 48MHz.

The temperature data sent to the PC as 4 digit integer number and it has to be in Celsius.
The main program has been broken down into following sections that make it easier to explain and understand.
1. Include USB Descriptor: The first and important part of this project is to include the USBdsc.c file to the main program which enables the program to use the USB library for the function that will be use later in main program file. This can be done in two ways either using MikroC IDE tool that enable user to add file to the project or simply added to main program using #include option follow by location of file.
2. Define Variable: The second part of each coding will be variable definition that is going to be used in coding. As it shows in code there are a number of unsigned

variables has been used to carry the sensor data and three arrays. One to store first read data from the sensor and another two to be used for write and read buffer, to get easily spot the write buffer name has been changed to the temperature that is going to be used to carry data to the PC.
3. Initialization function: In this part of the code, the PORTA was set as an input by assigning the TRISA to 0xFF and the PORTB as an output by assigning the TRISB to 0x00. The input was set as an analog and +5 reference by setting ADCON1 = 0x00 and analog to digital clock was set to Fosc/64, 8TAD by setting ADCON2 = 0xA6. The way to do this setting was described with the registers well in the PIC18F4550 part of this report.
4. Interrupt function: The interrupt function was used in this program to keep alive the USB link during communication or sending data. The function is keeping link alive by sending a message every 0.832ms and is placed on interrupt service routine (HID_InterruptProc). Timer0 is loaded with 100 that produce 0.832ms overflow time delay and enabling and disabling the interrupt all was described previously on the PIC18F4550 part of the report. 5. Removing blank function: This function is designed to remove extra blanks and digits, as only 4 digits of input data have to be screened out on the PC‟s screen.
6. Main loop: The initialization function (System_init) is the first function to be called in the main loop after initialization the interrupt function that contains of three functions is activated as following the first function (Interrupt_Dis) disabled all the interrupts, the second function (Timer0_init) activated timer0 as well as loading it with 100 to make 0.832ms delay and the third and last function (Interrupt_En) is to enable the interrupt. All setting part of these function has been describe in details previously in the PIC18F4550 part of this report.

The next function that has to be activated in the main loop is the HID USB. The HID enable function was described previously in the report used to enable the Human Interface Device before any other the USB functions. The function, as described before has two arguments write buffer (&Temperature) and read buffer (&Read_buffer). The write buffer was used to store and send input data to the host computer.
The next process was infinite loop which was added to the main loop as the microcontroller never stops the main program has to be in infinite loop.

The first operation is the infinite loop is to read the input voltage data from channel0 (AN0). In this design the input channel is connected to the potentiometer on the board. The input data from potentiometer will be stored in the “Vin” variable, was defined before in the initialization. The store data will be converted to voltage and get stored in the Voltage variable by following equation: Voltage = Vin x 5/1024 Next step is to convert this input voltage to temperature in Celsius that can be done by following equation: Celsius = (Voltage × 100) As the data needs to screen out as a 4 digit integer, the Celsius data was converted to integer and the result was stored on the Cint variable. The following equation was used to do that: Cint = (int) Celsius
To be able to test the software and checking the output data the PORTB was define in this part which enabled the user to output data on the PORTB LEDs for testing purposes. As the USB function can only send data in string, the integer input data was converted to string and was stored in the op array that defined in the beginning of the coding program. The op array can take up to 12 data sizes. As 4 digits has to screen out the remove blank function will be use in this line to take 4 first data from the op array and remove

leading blank of the array. The modify op array was stored it in the temperature buffer array (write buffer) to be send by the next function. The next function is Hid_Write (&Temperature, 4) which was used to send 4 digits to the PC using the USB bus.
As the program should updated every second to satisfy specification, in this part one second software delay was added to the program. This was done by following line of code.

Delay_ms (1000);

The program is in the infinite loop to get input data from a sensor and send it to the PC via the USB bus every one second.

Finally the Hid_Disable function was used to disable the human interface device at the end of the main loop however the program will be stock in the infinite loop after that. The main program for the microcontroller was shown in appendix 1.

Program testing:

After the program was written, the design code was checked using MikroC IDE software. The software has the HID terminal feature which enables the designer to output the data being send by the microcontroller.
The coding program was loaded into the microcontroller using the PICFlash software by connecting the USB programmer to the board and the PC. The USB cable was connected to the PC and the data was monitored from HID terminal by simply selecting device which was added when the USB cable was connected.

The data was output on the USB terminal every second as was expected. Figure (20) shows the data was output by the HID terminal.

2.2-PC Software:

The PC software part of this project is based on Visual Basic. The software program was written to achieve the detection of any USB connectivity operation as well as outputting the input data sent by the microcontroller on the USB bus as 4 bit integers.

The Visual Basic program was used in this project is base on the USB utility which known as Easy HID USB wizard.

The following software programs were used in the project to achieve the aim of screening out the data on the host computer‟s screen.

2.2.1-Easy HID USB wizard

Easy HID USB wizard is a software that can be use to generate an initial template file for the USB PIC and Visual Basic framework.

The software was developed by Mecanique and it can be downloading free of charge from their website (www.mecanique.co.uk).

The software was designed to work with the USB 2.0 and the user does not need to develop any driver to use it as the window XP operating system has the HID based USB driver. The generated code by Easy hid can be expand in such way that fulfils requirement. The following step was taken in order to generate the template code for the Visual Basic:
The first step was to load the zip file and install software by double clicking on set up icon.
After the software was installed, it can be run by double clicking on the icon that appeared on desktop after installation.
After running the software, the following window will pops up that needs to be filled up by company name, product name and serial number as it shown:

By clicking next, the next form will be display that has the Vender ID and Product ID as it shown in following form. The vender IDs are unique and issued by the USB implementer (www.usb.org). Mecanique has its own vender ID and can issue a set of Product IDs for each product with low cost to be use all over the world with the unique vender and product ID. In this project vender and product ID was selected as shown in Figure (22) which is use for testing purposes.

The next form that appear after clicking next, has different parameters such as polling interval for input and output as well as bus maximum power consumption. But the main important parameter in this part that has to be changed according to the project requirement is the input and output buffer size.
These sizes define the number of bits will be send or receive during a USB transaction between the PC and the Microcontroller. In this project both of the input and output was selected to be 4 bits as 4 bits input data are going to be receiving from the microcontroller.

In the next form the project name and location has to be selected as well as compiler and Microcontroller that is was selected to be used by the project. these part and location was selected as shown in Figure (24):

Clicking next will generate the Visual Basic template file in the selected directory which was defined in previous form as shown in Figure (25):

The file was generated by the Easy HID software has consist of a blank form (FormMain.frm), a module file (mcHIDInterface.BAS), and a project file (USBProject.vbp) as shown in Figure (26). The generated project file can be opened by the Visual Basic for more expansion and modification to satisfy the project requirements.

2.2.2-Microsoft Visual Basic 6.0:

Visual Basic is a programming language which can be use to develop window based applications and games.

There are numbers of the programming languages available for developing applications but the following benefits makes Visual Basic good software to use in this project:
It is easy to learn and use programming language compare with others (visual C++, etc).

The source availability for learning as it is much more popular compare with others.

There are number of tools (shareware & Freeware) on internet that can help to spare some programming time. Such as the Easy hid wizard who was used to create template file for the USB hid.
The template file was created with Easyhid was opened with Visual Basic by simply download and run Visual Basic6.

By selecting menu and open project (file> project> open project) the directory where project was created in previous part by Easy hid was selected and opened.
The opened project has two file (Mainform & HIDDLLInterface). The Mainform was modified and expanded in order to screen the input data as shown in the following Form and has the following controls.

Figure (27) illustrate the Form was displayed when the program was not connected to the device.

And when the device was connected to the PC using the USB cable the Form was appeared as shown in Figure (28).

In this part of report more details was given from the expansion part of the Mainform file program in order to display above output Form compare with the blank Form was created by the Easy hid.

a) The first part was added to the template file generated by Easy hid was to display messages on the Form that indicated Form was connected to HID and USB plugged, unplugged. This was obtained by dragged a label to the bottom part of Form where the message displays and was renamed to lblstatus and following message was added to the HID connect function in the Mainform coding part of program to get display as this function being executed by the program, when it is running.

lblstatus = “Connected to HID…” The following messages was added to the USB plugged and unplugged functions in order to display following messages in the case of connection or disconnection of the USB cable as shown here and in the appendix part of report. lblstatus = “USB Plugged…..” lblstatus = “USB Unplugged…..”
Adding these output messages to the end of each operation in the Mainform, will create output message whenever the program executing each specific function.

b) The next and important subroutine has been added the program was the onRead function used to catch data from the USB bus was sent by the microcontroller and display it on the screen.

The subroutine has a global variable (temperature) which stores 4 digits input data and one digit Report ID into 5 buffer inputs is sending from the microcontroller.

The first buffer (BufferIn (0)) always carry Report ID about the packages was sent from the microcontroller. The next 4 buffers (BufferIn (1), BufferIn (2), BufferIn (3), BufferIn (4)) are the actual 4 bits data sent as a string of character to the PC.

These characters were stored in string temperature variable and were displayed by textbox (txtno) in next line of coding program.

Progress bar was another technique was used to output temperature on the bar but as it can output only the integer data the output has to convert from the character to the integer.

All these operations were created and are shown in OnRead subroutine of Mainform appendix.
c) The next step was to add the command button in the bottom part of Form, the following subroutine (key_click) was added in order to stop and exit from the program. Form_Unload (0);
d) The labels such as the temperature measurement, Celsius and number were added to the Form to specify what each control does on the Form. By simply add a label and change its name to the name needed and located it next to the control.
e) At the labels and controls was modified to display as it needed by simply changing fonts, size, etc in their properties control page.

The main coding for the Form is shown in appendix3and interface in appendix 4.

2.2.3-USBTrace USB protocol analyzer

There are number of USB protocol analyzer in the market that can be use to check data transaction on the USB bus. Some are hardware based which make them more expensive and some are software based that make them cheaper compare with hardware based one.
The USBTrace is one of the software based analyzer that was developed by SysNcleus (www.sysnucleus.com), in this report the USBTrace USB protocol analyzer was used to monitored data on the USB bus in the case of project not operating as it was expected because of any problem. A limited time demo version of USBTrace is available on manufacture‟s web site.

The following steps shows in this section illustrate processes was taken place in order to use the software to monitor data was sent by the microcontroller to the PC using the USB bus:

The first step was to download and install program from manufacture‟s website.

The next step was to double click on the USBTrace icon on the desktop which runs the program and the Figure (29) window will appear on the screen.

The microcontroller was connected to the USB port of the PC which was detected by the program and a new human interface device was added to the left part of window.

The device was added in the previous step was selected by clicking on the box located next to the HID device.

The data is captured by clicking on the green arrow located on the top left of the menu.

The START OF LOG message was appears in the middle of the screen as the button was clicked and data was captured by the program every second as it was expected.
The captured data was indicated by green color this shown in Figure (30).

By moving the curser over each packet, the pop up window will appear that gives more information about packet and data has been send in hexadecimal.
By clicking on specific packet, the data value of data in Hexadecimal and ASCII will appear on bottom left of screen as shown in previous figure.
With this software after checking the data on the USB bus and comparing it with the data was expected to screen out on the PC‟s screen.

The designer can work out where the problem starts by observing and comparing the two data streams. The software can be great help to spot the problem in the design by simply monitoring and checking the data on the bus.

5) Results & Discussions:

The project was designed, built and tested. The test results concludes that the software functions as expected from design specification and it is satisfies all requirements. The test of the project was relatively trouble-free part of the project that can be done by going through following steps:

The first step was to construct hardware by placing the PIC18F4550 in the EasyPIC4 development board and activate the part of board is going to be used in the project.
The second step was to load the program into PIC18F4550 microcontroller by connecting board to the PC via the USB 2.0 programmer port and load the program using MikroC compiler and PICFlash2 software.
Next step was to run the visual basic program that detect human interface device and catch data and output it on the screen.
And finally connect the USB connector to the PC that establishes communication and sends data every second. As the microcontroller connects to the PC‟s port for the first time, a message should pops up on the bottom of screen to indicate the human interface device was recognized by the PC.
This can be checked through device manager too. The operation indicates the VIP and PID were set to the right values. Connecting the USB connector makes Visual Basic program to recognize the device and display out USB Plugged message and start to catching and displaying data on the Form.

The project works as it was expected and it satisfies the customer specification Every devices and software has been used in this project had advantages over other similar technology on the market, some described in following:
The microcontroller PIC18F4550 had 10-bit analog to digital conversion as well as the USB 2.0 technology built in one chip.
The EasyPIC4 development board was used as it had all the hardware components needed for the project all on one board built in and was used before for other designed project which made me more familiar to work with its operation compare with other development board.
MikroC compiler was used as it was easy to use and had the HID terminal that could generate the USB descriptor file as well as enabling user to communicate with the microcontroller through the USB bus without any other software.
Visual Basic software was used as the designer has knowledge of how to using software and it is easier to used and understand compare with other version such as Lab view and Visual C++.
Easy HID software was used to generate initial template file for Visual Basic framework which makes design easier.
USBTrace protocol analyzer was used as it is software base, easy to use and cheaper compare with other protocol analyzer in the market.

6) Conclusions & Future works:

The designed system can get input analog signal from a temperature sensor and output measured temperature in Celsius on the screen. The output data is updating every second. Using the USB 2.0 technology to send data from sensor to the host computer was one of the main challenges in this project which was involved with interfacing and protocols.
The following changing can be made to the system that can improve the system to be used by any other purposes that involves with sending data using USB 2.0 technology.

The potentiometer was used in the project to illustrate the analog signal as a temperature sensor. However in the case of where the sensor was defined, this can be change simply by setting the PORTA as an input and connect the sensor to the port. Choosing the PORTA as an input was done by simply disconnecting JP15 in A/D converter part of EasyPIC4 development board.

The system was designed to detect analog signal from the input, but in the case of the digital sensor is going to be used to the input port. The ADCON1 control register has to reconfigure to digital and some part of calculation in the microcontroller coding has to get change.

The input sensor can be increase as some device works with more than one sensor by specifying more input channels to read the data inputs and store them in larger write buffer array size that used to hold data on microcontroller part of program as well as expanding Visual Basic coding in such way that enable program to separate inputs data and output them in deferent textboxes on the form. Another way to do this is to use multiplexer to switch from one channel to another in each moment of time.

The design system can use wireless technology in order to establish communication between the device and the host computer to sending the input data from a sensor to the PC for more operation and store entire data in a database. The data however can be sent using apache software from one place to another for the user attention.

7) Project Planning:

This chart deals with planning and management of the project. Planning and management of any project is basically done following the basic structure as to „„WHERE YOU ARE‟‟ and „„WHERE DO YOU WANT TO GO‟„and finally giving an idea „„HOW TO GET THERE‟„.

Gantt chart:

The expected duration of the project is 12 Weeks, which is divided as mentioned above.
NOTE: The stipulated timings mentioned to complete the project might change as it is the maximum expected duration, and there is every chance to complete it early.

8) References and Appendices:

8.1. References:

1. USB Mass Storage by Jan Axelson 2. USB Complete by Jan Axelson 3. Advanced PIC Microcontroller Projects in C by Dogan Ibrahi

m 4. EasyPIC4 u

ser manual http://www.mikroe.com/pdf/easypic4/easypic4_manual.pdf 5. PIC18F4550 manual http://ww1.microchip.com/downloads/en/devicedoc/39632e.pdf 6. MikroC user manual http://www.mikroe.com/pdf/mikroc/mikroc_manual.pdf 7. Wikipedia website http://en.wikipedia.org/wiki/Universal_Serial_Bus 8. Visual Basic in easy step by Tim Anderson

8.2. Appendices:

Appendix 1: Main program For Microcontroller:

Appendix 2: USB Descriptor File:

Appendix 3: Visual Basic Main Form Code:

Appendix 4: HID Interface API Declaration File:

The post SKIN TEMPERATURE MEASUREMENT appeared first on PIC Microcontroller.

Hello everybody welcome back . Today I’m gonna tell how you can display temperature with bar graph on Graphic LCD using PIC microcontroller . The project is very simple to understand if you have concept of

Graphic LCD .The program in this project is written in C and Assembly level language &  the compiler used to write the C code is mikroC PRO for PIC V. 7.1.0 .You can download complete project (C and Asm file with proteus8 file ) from this link temperature on GLCd . 

Graphical Liquid Crystal (GLCD)

Graphical lcds are different from the ordinary alphanumeric  lcds, like 16×1 16×2 16×4 20×1 20×2 etc. They (ordinary) can print only characters or custom made characters. They have a fixed size for displaying a character normally 5×7 or 5×8 matrix. Where as in graphical lcd we have 128×64=8192 dots each dot can be lit up as our wish or we can make pixels with 8 dots ie. 8192/8=1024 pixels. We can design a character in a size which we need. More over we can make a picture on a graphical LCD as well. you can learn more about this LCD on this link Graphic LCD

LM35 Temperature Sensor

The LM35 temperature sensor is a semiconductor sensor. It is available in integrated circuit (IC) form. It has 3 pins and the IC is as shown below.

Working Principle of temperature sensor :

VT = kT/q

Features of LM35:

• Calibrated directly in Celsius scale ( Centigrade)
• Linear +10 mV/⁰C scale factor
• 5⁰C Ensured Accuracy (at 25⁰C)
• Works for -55⁰C to 150⁰C
• Operates in the range of 4V to 30V
• Less than 60µA design drain current
• Low impedance output, 0.1Ω for 1-mA load
• Low self heating, 0.8⁰C in still air

Display temperature on Graphic Liquid Crystal Display using PIC16F877A Microcontroller (Code)


// Glcd module connections
char GLCD_DataPort at PORTD;
sbit GLCD_CS1 at RC0_bit;
sbit GLCD_CS2 at RC1_bit;
sbit GLCD_RS at RB3_bit;
sbit GLCD_RW at RB4_bit;
sbit GLCD_EN at RB5_bit;
sbit GLCD_RST at RE2_bit;
sbit GLCD_CS1_Direction at TRISC0_bit;
sbit GLCD_CS2_Direction at TRISC1_bit;
sbit GLCD_RS_Direction at TRISB3_bit;
sbit GLCD_RW_Direction at TRISB4_bit;
sbit GLCD_EN_Direction at TRISB5_bit;
sbit GLCD_RST_Direction at TRISE2_bit;
// End Glcd module connections
char txt[4];
unsigned tmp;
void main() {
Glcd_Init();
Glcd_Fill(0);
ADC_Init();
while(1){
tmp = ADC_Read(0);
tmp = tmp/2.05;
ByteToStr(tmp, txt);
Glcd_Write_Text("o", 60,0, 1);
Glcd_Write_Text(txt, 35,1, 1);
Glcd_Write_Text("TEMP =", 0,1, 1);
Glcd_Write_Text("C ", 70,1, 1);
if (tmp>20) {Glcd_Box(10, 50, 20, 70, 1); }
if (tmp<20) {Glcd_Box(10,50, 20, 70, 0); } if (tmp>40) {Glcd_Box(20, 45, 30, 70, 1); }
if (tmp<40) {Glcd_Box(20, 45, 30, 70, 0); } if (tmp>60) {Glcd_Box(30, 40, 40, 70, 1); }
if (tmp<60) {Glcd_Box(30, 40, 40, 70, 0); } if (tmp>80) {Glcd_Box(40, 35, 50, 70, 1); }
if (tmp<80) {Glcd_Box(40, 35, 50, 70, 0); } if (tmp>100) {Glcd_Box(50, 30, 60, 70, 1); }
if (tmp<100) {Glcd_Box(50, 30, 60, 70, 0); } if (tmp>115) {Glcd_Box(60, 25, 70, 70, 1); }
if (tmp<115) {Glcd_Box(60, 25, 70, 70, 0); } if (tmp>130) {Glcd_Box(70, 20, 80, 70, 1); }
if (tmp<130) {Glcd_Box(70, 20, 80, 70, 0); } if (tmp>140) {Glcd_Box(80, 15, 90, 70, 1); }
if (tmp<140) {Glcd_Box(80, 15, 90, 70, 0); } if (tmp>145) {Glcd_Box(90, 10, 100, 70, 1); }
if (tmp<145) {Glcd_Box(90, 10, 100, 70, 0); }
}
}


Display temperature on Graphic Liquid Crystal Display using PIC16F877A Microcontroller (Schematic Diagram)

PROTEUS SCHAMATIC DIAGRAM WITH ANIMATION

Short Description

The code is very easy to understand . First we have defined Control and DATA pins of graphical LCD to PIC microcontroller . Then after we have displayed some text using function Glcd_Write_Text(“”, ,,); .Since we cannot write box using Glcd_Write_Text(); function we have to make our own box using the function Glcd_Box(x,y,-x,-y,on/off). These box are made to respective temperature and the box is used to represent the temperature . Thats all concept behind this project .
If you have any question about this project please comment below , if you like this project please share this .

The post Display temperature on Graphic Liquid Crystal Display using PIC16F877A Microcontroller appeared first on PIC Microcontroller.

Researchers at the University of Warwick in the UK have developed sensors which measure the internal temperature and electrode potential of Lithium batteries. The technology is being developed by the Warwick Manufacturing Group (WMG) as a part of a battery’s normal operation. More intense testings have been done on standard commercially available automotive battery cells.

If a battery overheats it becomes a risk for critical damage to the electrolyte, breaking down to form gases that are both flammable and can cause significant pressure build-up inside the battery. On the other hand, overcharging of the anode can lead to Lithium electroplating, forming a metallic crystalline structure that can cause internal short circuits and fires. So, overcharging and overheating of a Li-ion battery is hugely damaging to the battery along with the user.

The researchers at Warwick developed miniature reference electrodes and Fiber Bragg Gratings (FBG) threaded through a strain protection layer. An outer coat of Fluorinated Ethylene Propylene (FEP) was applied over the fiber, ensuring chemical protection from the corrosive electrolyte. The end result is a sensor which has direct contact with all the key components of the battery. The sensor can withstand electrical, chemical and mechanical stress faced during the normal operation of the battery while still giving accurate temperature and potential readings of the electrodes.

The device includes an in-situ reference electrode coupled with an optical fiber temperature sensor. The researchers are confident that similar techniques can also be developed for use in pouch cells. WMG Associate Professor Dr. Rohit Bhagat said,

Read more: Newly Developed Internal Temperature Sensor For Li-ion Battery Enables 5x Faster Charging

The post Newly Developed Internal Temperature Sensor For Li-ion Battery Enables 5x Faster Charging appeared first on PIC Microcontroller.

In this blog there are some topics talking about the DHT11 relative humidity and temperature sensor and how to interface it with different types of PIC microcontrollers. The datasheet of the DHT11 sensor shows its characteristics and how it works.

Also the following topic shows the DHT11 timing and how to simulate it using Proteus:
Interfacing PIC16F877A with DHT11 (RHT01) sensor Proteus simulation
This topic shows how to interface this sensor with the microcontroller PIC12F1822. This microcontroller has only 8 pins and 6 of them can work as an I/O pins.
An LCD is used to display temperature and relative humidity values. A shift register is used to make a 3-wire LCD as shown at the following link;
Interfacing PIC12F1822 microcontroller with LCD display
Therefor for this simple project we need 3 data lines for the LCD and 1 line for the DHT11 sensor which means we need 4 I/O pins.
Components List:

• PIC12F1822 Microcontroller
• DHT11 (RHT01) Sensor
• 1602 LCD
• 74HC595 Shift Register (74HC164 or CD4094 can do the job)
• 10K Variable Resistor
• 4.7K Resistor
• +5V Power Supply
• Breadboard
• Jumper Wires

Interfacing PIC12F1822 with DHT11 sensor circuit:

The shift register data line is connected to RA0 pin and the clock line is connected to RA1 pin. LCDs enable pin is connected to pin RA3.
The internal oscillator of the PIC12F1822 microcontroller is used.
To see how to use 74HC164 or CD4094 instead of 74HC595 go to the link above.

The DHT11 sensor has 4 pins:
VCC : Positive power supply (+5V)
DATA : Sensor data input and output
NC : Not connected terminal
GND : Ground (0V)
A pull-up resistor must be added between the DHT11 data pin and VCC (+5V) pin as shown in the circuit schematic (4.7K ~ 10K).

Read more: DHT11 Interfacing with PIC12F1822 microcontroller

The post DHT11 Interfacing with PIC12F1822 microcontroller appeared first on PIC Microcontroller.

This topic shows how to interface DHT22 (AM2302, RHT03) digital relative humidity and temperature sensor with PIC16F84A microcontroller, and how to simulate this interfacing using Proteus.
Note that for the simulation Proteus version should be 8.1 or higher. With these versions there is no need to install Proteus DHT22 library, it is included with the software, so don’t waste your time searching for dht22 library, dht22 Proteus library, dhtxx.mdf or dht22 module for Proteus, just use Proteus version 8.1 or higher.

About DHT22 (AM2302, RHT03) relative humidity and temperature sensor:
The DHT22(AM2302, RHT03) sensor comes in a single row 4-pin package and operates from 3.3 to 5.5V power supply. It can measure temperature from -40-80 °C with an accuracy of ±0.5°C and relative humidity ranging from 0-100% with an accuracy of  ±2%. The sensor provides fully calibrated digital outputs for the two measurements. It has got its own proprietary 1-wire protocol, and therefore, the communication between the sensor and a microcontroller is not possible through a direct interface with any of its peripherals. The protocol must be implemented in the firmware of the MCU with precise timing required by the sensor.
The following timing diagrams describe the data transfer protocol between a MCU and the DHT22 sensor. The MCU initiates data transmission by issuing a “Start” signal. The MCU pin must be configured as output for this purpose. The MCU first pulls the data line low for at least 18 ms and then pulls it high for next 20-40 us before it releases it. Next, the sensor responds to the MCU “Start“  signal by pulling the line low for 80 us followed by a logic high signal that also lasts for 80 us. Remember that the MCU pin must be configured to input after finishing the “Start“ signal. Once detecting the response signal from the sensor, the MCU should be ready to receive data from the sensor. The sensor then sends 40 bits (5 bytes) of data continuously in the data line. Note that while transmitting bytes, the sensor sends the most significant bit first.

Data consists of decimal and integral parts. A complete data transmission is 40bit, and the sensor sends higher data bit first.
Data format: 16 bits RH data + 16 bits temperature data + 8bit check sum. If the data transmission is right, the check-sum should be the last 8bit of “MSB 8-bit RH data + LSB 8-bit RH data + MSB 8-bit temperature data + LSB 8-bit temperature data”.
The DHT22 is a digital sensor so it sends 1’s and 0’s, but it is very important to know how it sends the digital data. The figure below shows how the sensor sends its information:

Example: MCU has received 40 bits data from AM2302 as
0000 0010 1000 1100 0000 0001 0101 1111 1110 1110
16 bits RH data 16 bits T data check sum
Here we convert 16 bits RH data from binary system to decimal system,
0000 0010 1000 1100 → 652
Binary system Decimal system
RH=652/10=65.2%RH
Here we convert 16 bits T data from binary system to decimal system,
0000 0001 0101 1111 → 351
Binary system Decimal system
T=351/10=35.1℃
When highest bit of temperature is 1, it means the temperature is below 0 degree Celsius.

Example: 1000 0000 0110 0101, T= minus 10.1℃
16 bits T data
Sum=0000 0010+1000 1100+0000 0001+0101 1111=1110 1110
Check-sum=the last 8 bits of Sum=1110 1110
Interfacing PIC16F84A with DHT22(AM2302, RHT03) sensor circuit:
The following circuit schematic shows complete project circuit.

Read more: PIC16F84A + DHT22(AM2302, RHT03) sensor Proteus simulation 

The post PIC16F84A + DHT22(AM2302, RHT03) sensor Proteus simulation appeared first on PIC Microcontroller.

timing diagrams describe the data transfer protocol between a MCU and the DHT11 sensor. The MCU initiates data transmission by issuing a “Start” signal. The MCU pin must be configured as output for this purpose. The MCU first pulls the data line low for at least 18 ms and then pulls it high for next 20-40 us before it releases it. Next, the sensor responds to the MCU “Start“  signal by pulling the line low for 80 us followed by a logic high signal that also lasts for 80 us. Remember that the MCU pin must be configured to input after finishing the “Start“ signal. Once detecting the response signal from the sensor, the MCU should be ready to receive data from the sensor. The sensor then sends 40 bits (5 bytes) of data continuously in the data line. Note that while transmitting bytes, the sensor sends the most significant bit first.

Data consists of decimal and integral parts. A complete data transmission is 40bit, and the sensor sends higher data bit first.

Data format: 8bit integral RH data + 8bit decimal RH data + 8bit integral T data + 8bit decimal T data + 8bit check sum. If the data transmission is right, the check-sum should be the last 8bit of “8bit integral RH data + 8bit decimal RH data + 8bit integral T data + 8bit decimal T data”.

The DHT11 is a digital sensor so it sends 1’s and 0’s, but it is very important to know how it sends the digital data. The figure below shows how the sensor sends its information:

Read more: PIC16F84A + DHT11 Proteus simulation

The post PIC16F84A + DHT11 Proteus simulation appeared first on PIC Microcontroller.

The last interfacing of the PIC16F887 microcontroller and DS3231 RTC is the building of a simple real time clock and calendar with two buttons for setting time and date. Project link is the one below:
Interfacing DS3231 with PIC16F887 microcontroller
In this topic I’m going to add 2 alarms and temperature monitor to the previous project since the DS3231 has 2 alarm functions and temperature sensor with an accuracy of ±3°C (for more information read the DS3231 datasheet).

Hardware Required:

• PIC16F887 microcontroller
• 20×4 LCD screen
• 10K ohm variable resistor
• 330 ohm resistor
• LED
• 3 x push button
• 5V supply source
• Breadboard
• Jumper wires

DS3231 board contains the following components:

• DS3231 RTC – datasheet
• 3 x 4.7K ohm resistors
• 0.1uF ceramic capacitor
• 3V coin cell battery

The circuit:
Circuit schematic diagram is shown below.

In this project I used the DS3231 board, this board basically contains the main chip which is the DS3231, pull-up resistors (4.7K) of SCL, SDA and INT/SQW lines and coin cell battery holder. There is also 24C32 EEPROM and some other resistors (not used in this project).
The DS3231 board is supplied with 5V as the microcontroller and the 2004 LCD, there are 3 data lined connected between this board and the PIC16F887 MCU, SCL line is connected to pin RC3, SDA is connected to pin RC4 and INT line is connected to pin RB0 which is the external interrupt pin of the PIC16F887 MCU. The DS3231 interrupts the microcontroller when there is an alarm.

In the circuit there are 3 push buttons: B1, B2 and B3. These buttons are used to set time, calendar and alarms. Time and calendar can be adjusted with B1 and B2, button B1 selects time or date parameter (time parameters: hours and minutes; calendar parameters: day, date, month and year) and B2 increments the selected parameter. The button B3 and B2 adjust alarm1 and alarm2 parameters (hours, minutes and ON/OFF), button B3 selects the parameter and B2 increments the selected parameter.
There is an LED connected to pin RB4, this LED is used as an alarm indicator (alarm1 or alarm2), so if there is an alarm the DS3231 pulls down the INT pin which interrupts the microcontroller and the microcontroller turns the LED ON, here button B2 turns both the LED and the occurred alarm OFF.
In this project the PIC16F887 MCU uses its internal oscillator and MCLR pin function is disabled.

Read more: Real time clock and temperature monitor using PIC16F887 and DS3231

The post Real time clock and temperature monitor using PIC16F887 and DS3231 appeared first on PIC Microcontroller.

This small topic shows the circuit diagram and CCS C code of the interfacing of LM35 temperature sensor with PIC18F4550 microcontroller.

The LM35 temperature sensor is three pin device (VCC, OUT and GND) with an output voltage linearly related to Centigrade temperature. Since the LM35 output varies with dependent to the temperature we need ADC (Analog-to-Digital Converter) module to measure this voltage. The ADC module converts analog data into digital data.
The LM35 output has linear +10mV/°C scale factor means the following:
If the output voltage =   10mV —> temperature =   1°C
If the output voltage = 100mV —> temperature = 10°C
If the output voltage = 200mV —> temperature = 20°C
If the output voltage = 370mV —> temperature = 37°C
and so on.
LM35 Futures (from datasheet):

• Calibrated Directly in ° Celsius (Centigrade)
• Linear + 10 mV/°C Scale Factor
• 0.5°C Ensured Accuracy (at +25°C)
• Rated for Full −55°C to +150°C Range
• Suitable for Remote Applications
• Low Cost Due to Wafer-Level Trimming
• Operates from 4 to 30 V
• Less than 60-μA Current Drain
• Low Self-Heating, 0.08°C in Still Air
• Nonlinearity Only ±¼°C Typical
• Low Impedance Output, 0.1 Ω for 1 mA Load

Hardware Required:

• PIC18F4550 microcontroller
• LM35 temperature sensor  — datasheet
• 1602 LCD screen
• 10K ohm variable resistor
• Breadboard
• 5V voltage source
• Jumper wires

Interfacing PIC18F4550 with LM35 sensor circuit:

The output of the LM35 temperature sensor is connected to analog channel 0 (AN0) of the PIC18F4550 microcontroller.
In this example the MCU uses its internal oscillator and MCLR pin function is disabled.
Interfacing PIC18F4550 with LM35 temperature sensor C code:
The C code below was tested with CCS PIC C compiler version 5.051.
Reading voltage quantity using the ADC gives us a number between 0 and 1023 (10-bit resolution), 0V is represented by 0 and 5V is represented by 1023. Converting back the ADC digital value is easy and we can use the following equation for that conversion:

Voltage (in Volts) = ADC reading * 5 / 1023
Multiplying the previous result by 100 (LM35 scale factor is 10mV/°C = 0.01V/°C) will gives the actual temperature:
Temperature(°C) = ADC reading * 0.489
where 0.489 = 500 / 1023
The complete C code is the one below.

Read more: Interfacing LM35 temperature sensor with PIC18F4550 microcontroller

The post Interfacing LM35 temperature sensor with PIC18F4550 microcontroller appeared first on PIC Microcontroller.

The Apollo Lake SoC has already be used in several boards and modules. Avalue, a technology company that has launched several single board products and with focus on innovative embedded products has recently launched an embedded platform called the “ESM-APLC“, a Linux-ready COM that provides support for either the Intel Apollo Lake Celeron®N3350 or Pentium®N4200 SoC.

Avalue which isn’t new to the Apolo Lake board designs released the EQM-APL last fall, a Qseven module based on the Intel’s Apollo Lake. The ESM-APLC module to some extent inherit some similar attributes of the EQM-APL module, just like the EQM-APL module allows one to use between the Apollo Atom, Celeron or the Pentium SoC, the ESM-APLC does the same with the major exemption of the Atom SoC. The ESM-APLC drops the Apollo Lake Atom SoC in its build.

The EQM-APLC module measures at 95 x 95mm in a Type6 style shape COM Express Compact module. It is equipped with the Intel Apollo lake Pentium N4200 1.1GHz  or Celeron N3350 1.1GHz  SoC Processors both of which have a low 6W TDP. ESM-APLC supports one 204-pin DDR3L 1866 SO-DIMM (up to 8GB via single socket), and the module supplies up to 64GB of optional onboard eMMC 5.0. Extensive I/O support including 8 x USB 2.0, 4 x USB 3.0, 2 x SATA III, 1 x UART, 1 x 8-bit GPIO, 1 x SMBus, 1 x LPC and 1 x I2C.

ESM-APLC provides a triple display interface option; it supports several graphics interfaces including dual-channel 18/24-bit LVDS with support up to 1920 x 1200 @60Hz, VGA Support up to 1920 x 1200 @60Hz, HDMI support up to 3840×2160 @30Hz and DP support 4096×2160 @60Hz. HD Audio is not left behind in this wealth of features.

The module expansion port comes with 3x PCIe GEN2 x1 interfaces and an optional 4 PCIe x1 or 1 PCIe x4 that comes at the cost of sacrificing the Ethernet. The module is expected to work optimally in 0 to 60°C operation with a wide range of temperature input (9- 19V AT/ATX input with ACPI 3.0. TPM 2.0 is optional). ESM-APLC is ideal for customers who need optimized processing and graphics performance with low power consumption in a long product life solution, such as embedded board, MID/UMPC, Microserver/Server and Consumer Electronics.

Read more: Avalue ESM-APLC – An Apollo Lake board that gives option for the Celeron®N3350 or Pentium®N4200 SoC

The post Avalue ESM-APLC – An Apollo Lake board that gives option for the Celeron®N3350 or Pentium®N4200 SoC appeared first on PIC Microcontroller.

VersaLogic has released a rugged, lasting, simple-to-use and ready-for-deployment Zebra VL-EPC-2701 board. The Zebra single board computer is a complete Arm-based embedded computer. It features several models that are available with power-efficient, single- or dual-core i.MX6 CPUs. The Arm-based Single Board computer comes in two models; which features either NXP i.MX6 Solo (single core), or the i.MX6 DualLite (dual core) processors.

With its 95 x 95 mm size, the compact board is easy to mount and perform future upgrades. Not only that, Zebra conforms to the size and mounting points of the industry standard COM Compact format. The Zebra NXP’s single-core i.MX6 Solo comes with an onboard 512MB DDR3L RAM, while the dual-core DualLite comes with a built-in 1GB RAM, both of which are expandable up to 4GB RAM. The Zebra offers an optional 8GB microSD card with Linux and supports Linux distributions and OSes that are compatible with the Cortex-A9 based i.MX6.

This embedded computer boards provide connectivity via Gigabit Ethernet, USB, and CAN bus interfaces, as well as HDMI video support. They also provide a MikroBUS socket for expandability, and additional on-board I/O including I2C, audio, SPI, and GPIO. The Zebra embedded computer board has been programmed for a ready off-the-shelf deployment into demanding industrial, defense, and aerospace applications requiring rugged, durable, power efficient, industrial temperature.

Unlike many Arm-based modules, VersaLogic’s Zebra comes uniquely in some ways. The new product is a complete board-level computer. It requires neither additional carrier board nor, companion boards nor, connector break-out boards, or other add-ons to function. Since it was built to be exceedingly efficient, rugged and lasting, Zebra is rated for full industrial temperature operation of -40° to +85°C. Even at that, it consumes less than 3W of power during operation.

Read more: Zebra SBC – ARM based Single Board Computer from VersaLogic

The post Zebra SBC – ARM based Single Board Computer from VersaLogic appeared first on PIC Microcontroller.

Xbee based temperature and gas monitoring system using pic microcontroller is a system that could be used for monitoring or controlling the temperature or gas automatically of any room, public place or storage place such as vegetable storage or fruit storage place. If we analyze the current situation of world then we can easily examine that in this busy world, no one has a time to switch on or off the electric appliances such as home or public place appliances. As a result, these appliances are running continuously therefore the home or public place expenses are increasing day by day. To overcome this problem here we have designed a system that is called a Xbee based temperature and gas monitoring system using pic microcontroller.

This system has designed with the help of pic18F452 microcontroller, Xbee module, DS18B20, USB to UART module, LCD display, transformer, bridge rectifier and voltage regulator. This system has divided into two ends one is called transmitter end from where temperature or gas data is send and second one is called receiver end from where data is received through user computer. By using this system, the user can easily know the temperature or gas data at his computer automatically and then switch on or off the respective electric appliances. This system is more compact, more reliable and less costly as compared to other systems. The block diagrams of transmitter and receiver ends of this Xbee based temperature and gas monitoring system using pic microcontroller with respective components are shown is figure 1 and 2.

Transmitter End Block Diagram of XBee Based Temperature and Gas Monitoring System Using Pic Microcontroller

Here is the transmitter end block diagram of Xbee based temperature and gas monitoring system using pic microcontroller with their essential components,

Figure 1 Transmitter End Block Diagram of Xbee Based Temperature and Gas Monitoring System Using Pic Microcontroller

Transmitter End Working of XBee Based Temperature and Gas Monitoring System Using Pic Microcontroller

The transmitter end of this Xbee based temperature and gas monitoring system using pic microcontroller is directly coupled with 220V ac supply. Because the whole system consists of electronic components therefore ac voltages are step down into 6V through step down transformer then these are converted into dc through bridge rectifier. After that, these voltages are regulated into 5V dc through voltage regulator LM 7805. The whole components of this system are powered up through voltage regulator. Here we would demonstrate this system only for temperature measurements. For temperature measurement, the temperature is sensed through temperature sensor DS18B20.

After sensing the temperature, this sensor gives the logic high signal to microcontroller which is main intelligent control of this system. It is programmed in c language with the help mikro/c software and is interfaced with Xbee module and LCD display. After that, this controller gives the logic high signal to Xbee module, which is basically a tiny chip used for communication purposes between two devices wirelessly. Microcontroller also displays the temperature data on LCD display. Two Xbee modules are used in this system one is used at transmitter end for transmitting the temperature data and other one is used at receiver end for receiving the temperature data.

Read more: XBee Based Temperature and Gas Monitoring System Using Pic Microcontroller

The post XBee Based Temperature and Gas Monitoring System Using Pic Microcontroller appeared first on PIC Microcontroller.

IOT based temperature data logger using esp8266 and pic microcontroller: Hi everyone I hope you are learning about embedded systems and working on embedded systems based projects. Internet of things is a very popular topic now a days among engineering students and professionals. Many Engineering students works on IOT based projects.In today’s project based on pic microcontroller, you will learn how to make IOT based temperature data logger using pic microcontroller and esp8266 wifi module. ThingSpeak will be used as a live monitoring server of data. You will learn how to send data to a server like thingspeak.com. In this project, we will measure temperature with LM35 temperature sensor using pic microcontroller and we will interface esp8266 wifi module with pic microcontroller. Wifi module is used to send data to server thingspeak. We will plot temperature in the form of graph on thingspeak.

The post IOT based temperature data logger using esp8266 and pic microcontroller appeared first on PIC Microcontroller.

Firefly has launched a new SODIMM-style, 67.6 x 40mm Core-PX3-SEJ module that runs Android 5.1 or Ubuntu 15.04 on a Rockchip PX3-SE. It’s a new 1.3GHz, quad-core, Cortex-A7 SoC. The 40 USD module is available in a 1GB RAM/8GB eMMC configuration on a $120, 117 x 85mm Firefly-PX3-SE development board. Other memory configurations may also be available soon.

The PX3-SE SoC gives the module a sandwich-style dev board and increases the operating temperature to -20 to 80℃ range. The Core-PX3-SEJ module is praised for its anti-corrosion gold finger expansion connector, and the dev board for its “double stud fixed” design.

Rockchip’s PX3-SE SoC was announced in May 2017. The main target of this SoC is Linux and Android-driven “mobile vehicle interconnect solutions.” The quad-A7 SoC implements a Mali-400 GPU and supports HD video.

The Firefly-PX3-SE board’s 2.4GHz WiFi and Bluetooth 4.0 are supplied separately from the compact Core-PX3-SEJ COM. Despite the lack of 4K support, there are a numerous media interfaces, including a variety of audio features. There are HDMI, CVBS, MIPI-DSI or LVDS, and a DVP camera interface. Analog, SPDIF, and I2S audio connections are available along with an onboard mic and a “phone” I/O port.

The Firefly-PX3-SE board is further provided with a GbE port, 4x USB 2.0 host ports, a micro-USB OTG port, and an 84-pin expansion header. RTC, debug, and IR are also onboard.

Specifications summary for the Firefly-PX3-SE development board with Core-PX3-SEJ module:

• Processor : Rockchip PX3-SE (4x Cortex-A7 cores @ 1.3GHz); Mali-400 MP2 GPU
• Memory:
  • 256MB, 512MB, 1GB, or 2GB DDR3 RAM (via Core-PX3-SEJ)
  • 4GB to 64GB eMMC flash (via Core-PX3-SEJ) with 4GB and 8GB default SKUs
  • MicroSD slot
• Wireless:
  • 2.4GHz 802.11b/g/n with antenna
  • Bluetooth 4.0 with BLE
• Networking: Gigabit Ethernet port (Realtek RTL8211E)
• Display & media:
  • HDMI port with audio
  • MIPI-DSI or LVDS LCD interface
  • CVBS with video and audio
  • DVP camera interface for up to 5MP
  • 3.5mm analog audio input jack
  • SPDIF optical output
  • Microphone input
  • I2S audio I/O
  • A phone I/O interface
• Other I/O:
  • 4x USB 2.0 host ports
  • Micro-USB 2.0 with OTG
  • Serial console debug
  • 84-pin expansion header (MIPI, LVDS, PWM, SPI, UART, ADC, I2C, I2S, GPIO)
• Other features: RTC with battery; IR receiver; power, reset, recover buttons; acrylic rack kit
• Power: 5V, 2A (via DC jack); PMU (via Core-PX3-SEJ)
• Dimensions: 117 x 85mm (with 67.6 x 40mm integrated COM)
• OS Support: Android 5.1; Ubuntu 15.04; includes Linux Buildroot/Qt

Read more: Firefly’s Latest Core-PX3-SEJ COM Runs Ubuntu or Android

The post Firefly’s Latest Core-PX3-SEJ COM Runs Ubuntu or Android appeared first on PIC Microcontroller.

The battle of the world smallest computer is something the researchers at the University of Michigan don’t attempt to give up anytime soon with the introduction of the Michigan Micro Mote, a computer smaller than a grain of rice.

The Michigan Micro Mote has helped researchers at the University of Michigan remain top in the competition of the creation of the world’s smallest computer. IBM took the title in March 2018 with the release of their 1mm x 1mm computer that measured smaller than a grain of fancy salt at its Think 2018 conference; however, the Michigan Micro Mote has put the University of Michigan back at the top.

One major talk about the new computer built and even the previous one by IBM is if the so-called computer can be called a Computer. Reason being, it is hard to decide if the micro mote is a computer or not since they don’t satisfy some computer requirements like the ability to keep data when power runs out.

According to David Blaauw, a professor of Electrical and Computer Engineering at the University of Michigan,

We are not sure if they should be called computers or not. It’s more of a matter of opinion whether they have the minimum functionality required.

Be low are the features and capabilities of the Micro Mote:

• It cannot retain programming and data once there is a power loss
• This super tiny computer uses photovoltaics: a way of converting light to electricity to enable an exchange of data.
• It has a base station which provides light for power and programming. It also receives data. Light from the base station and the transmission LED (Light Emitting Diode) creates currents in the tiny circuits.
• There are wireless transmitters for transmitting data with visible light.
• Presence of precision sensor to convert temperature into time intervals that come with electronic pulses.
• The Michigan Micro Mote has a LED, system memory and a processor.
• Dimensions of the computer are 0.3 by 0.3 by 0.3mm. It is shorter than a grain of rice.
• Can measure temperature in super tiny regions such as a cluster of cells, with an accuracy of 0.1 degree Celsius.

Read more: Michigan Micro Mote – The World’s Smallest Computer

The post Michigan Micro Mote – The World’s Smallest Computer appeared first on PIC Microcontroller.