Experiments with PIC16F628A

H-Bridge is a very popular application circuit for dc motor control. It uses BJTs or MOSFETs to switch on the dc motor in clockwise or counterclockwise direction. This tutorial describes the classical H-bridge circuit and how to interface it with a PIC microcontroller to operate a DC motor.

This project shows how to make a simple programmable digital timer switch with a PIC16F628A microcontroller. The timing schedule for the relay switch can be programmed through 4 push buttons. The program menu, the status of the relay switch and time information is shown on a character LCD.

This is a Christmas decoration project using LEDs and PIC microcontroller. The red color LEDs are used to construct a Christmas greeting and the letters in the message are individually controlled through the microcontroller's I/O pins.

This breadboard module is for PIC16F628A microcontroller and it provides access to the I/O ports and the power supply pins through male headers that can be easily inserted into a breadboard. This board will make protyping easier as the external oscillator, reset, and ICSP circuits are already implemented in the module. The layout of the module is shown below. You can construct this board on a general purpose prototyping circuit board.

If your digital multimeter does not have features for testing diodes and transistors, hold on, here's a project that describes how you can construct one by yourself. This project is based on a PIC16F688 microcontroller and uses the simple concept of unidirectional conduction of PN juction to find if the diode or transistor is good or bad. The test results are displayed on a character LCD. It also shows the type of the transistor (NPN or PNP) as well as which of the PN junctions are open or short in a faulty transistor.   Source: http://embedded-lab.com/blog/

Introduction Tachometer is a device that gives you the information about the rotational speed of any shaft or disc. It usually measures the speed in revolutions per minute (RPM). Today we are going to make a simple tachometer that could measure the rotation speed of a disk without making any physical contact (that's why it is contact less) with the rotating object. The range of this tachometer is 0 - 9999 RPM and displays the RPM on a multiplexed 4-digit seven-segment display. Of course, we are going to do this project on our usual PIC16F628A development board. Infrared sensor Contact-less measurement of RPM will be achieved through an IR sensor. An IR diode will send a beam of infrared towards the rotating disc, and any reflected pulse will be received by a photo diode. The resistance of a photo diode drops drastically when exposed to infrared. An infrared is reflected by a white surface and absorbed by the dark ones. The test disc for this project is shown below. You can see ...

Actually this is the another version of my older DVM project that was based on PIC12F683. The older version displays the measured voltage on a LCD that is driven serially by PIC12F683 using 3 I/O pins. The new one uses PIC16F688 microcontroller that doesn't require the serial driver as it has got enough pins to drive a LCD directly in 4-bit mode. The theory and math is just the same. You can read my PIC12F683 version of this project here . Circuit Diagram Circuit on breadboard