pic microcontroller projects

Description: The dual-channel thermometer is a simple project based on a PIC microcontroller with ADC capabilities. It is an inexpensive thermometer that utilizes low-cost components and does not require high-sensitivity or expensive sensors. Instead, it employs a simple silicon diode as the temperature sensor. The dual-channel feature allows for temperature measurement from two different locations, with the results displayed on a PC using C#.NET programming. To minimize costs, the project interfaces with the PC solely through a parallel port, eliminating the need for additional display devices such as an LCD or seven-segment display. The circuit for this project is straightforward, utilizing commonly available components from the local market. Two 1N4148 diodes serve as temperature sensors, with their anodes connected to VCC via 1kΩ resistors, which provide sufficient current for the diodes. The anodes of the diodes are also connected to the ADC channels of the PIC microcontroller, specifically channels 2 and 3. To measure temperatures from two different locations, the diodes can be placed in those locations. The ADC output from the PIC is sent to PORTB, which is connected to the data port of the parallel port. To obtain two different values from the ADC inputs, a control port of the parallel port is used for switching between the two ADC inputs. The programming of the PIC is performed using the mikroC compiler, which simplifies the coding process. A demo version of the compiler is available for download from their website. The firmware for the dual-channel thermometer is also provided.

The dual-channel thermometer circuit employs a PIC microcontroller, specifically one with integrated Analog-to-Digital Converter (ADC) capabilities, to facilitate temperature measurements. The choice of the 1N4148 diode as a temperature sensor is based on its adequate sensitivity and availability, making it an ideal low-cost solution for this application. The circuit configuration begins with the connection of two 1N4148 diodes, which are strategically placed in the desired measurement locations. Each diode's anode is connected to a positive voltage supply (VCC) through a 1kΩ resistor, ensuring that the diodes receive sufficient current for accurate operation.

The output from each diode is routed to specific ADC channels on the PIC microcontroller—channels 2 and 3—allowing the microcontroller to read the voltage drop across each diode, which corresponds to the temperature at their respective locations. The ADC converts this analog voltage into a digital signal, which is then sent to PORTB, a parallel port data bus on the PIC. This connection enables the microcontroller to transmit the digital temperature readings to a PC.

To facilitate the selection of the appropriate ADC channel for reading, the control port of the parallel port is utilized. This control mechanism allows the microcontroller to switch between the two ADC inputs, ensuring accurate readings from both sensors. The data is processed and displayed on a PC using a C#.NET application, which interprets the digital signals received from the PIC.

Overall, this project exemplifies an efficient and cost-effective approach to temperature measurement using commonly available electronic components, leveraging the capabilities of the PIC microcontroller and parallel port communication for data display and analysis. The use of mikroC for programming simplifies the development process, allowing for straightforward implementation and testing of the firmware required for the dual-channel thermometer.Dual channel thermometer is simple PIC ADC based project. It`s a inexpensive thermometer with low cost components. Don`t used any high sensitive or high cost sensor for thermometer. I am using only simple silicon diode. Dual channel means this thermometers have two sensor for pinking temperature from two different place and it displayed on PC usin g C#. Net programming. To reduce cost I am used only parallel port for interfacing with PC. There is no any additional display devices such as LCD or seven segment display etc. Simply I draw circuit for this project. You can see that there is no any high cost devices, they are only commonly available components in local market. Two 1N4148 diode is used as temperature sensor. The anode of diodes connecting to VCC through a1K resistors, these resistors are sufficient to flow current through the diodes.

Then connect anode of the diode to PIC ADC channels. I am using channel 2 and 3. If you want to measure temperature from two different place just place these diodes to two different places. The ADC output from the PIC put to PORTB. The PORTB connected to data port of the parallel port. To measure two different values from ADC input we are using a control port of the parallel port for switching between two different ADC input.

I am using mikroC compiler for PIC programming. It is very easy to coding in mikroC. You can download demo version from their website. Here is PIC fimware for dual channel thermometer.