Bargraph-Voltmeter-Featured-Image

Bargraph Voltmeter

A simple bargraph voltmeter can be built using 2x16 LCD or compatible VFD display. For Arduino version click here. This design utilizes PIC16F877 microcontroller and its ADC block to convert 0 – 5V input voltage to a binary number shown ...
Arduino-Photoresistor-Relay-Control-with-PCF8591-Module-Featured-Image

Arduino Photoresistor Relay Control with PCF8591 Module

Relay controlled by light intensity can be implemented using Arduino UNO compatible board. In this case Keyestudio UNO R3 and AD/DA module with PCF8591 chip. Similar simpler design is available here. On this particular module a photoresistor and a potentiometer ...
3 Digit Dot Matrix Display SPI

3 Digit Dot Matrix Display SPI

3 Digit Dot Matrix Display with SPI interface is an advanced version of recently published 7x5 Dot Matrix Character Generator project. This design is more complex as it contains 4 microcontrollers. Three PIC16F88 were used to control 7x5 Dot Matrix Displays, ...
1Hz Clock Generator Featured Image PIC16F876A

1Hz Clock Generator using PIC16F876

In this article we’ll see how to generate 1 Hz clock with PIC16F876/877 PIC microcontrollers. 3 different approaches will be demonstrated. The most basic solution is to use nested loops to “waste” enough instruction cycle time in order to produce ...
Temperature Controlled Fan Featured Image

Temperature Controlled Fan

Voltage  control is done by LM317 and 2 NPN 2N3904 transistors, see design schematic. Fan controller was tested with SWiF2-800 Coolink fan, however any standard case fans should work.Only basic calibration is required. 1 - Adjust potentiometer connected to LM317 till you ...
Raspberry-Pi-3-Digit-LED-7-Segment-Countdown-Timer-Featured-Image

Raspberry Pi 3 Digit LED 7-Segment Countdown Timer

Multiplexing 7-Segment display scheme with Raspberry Pi as described here can be used as a basis for more complex projects. By adding 4x4 keypad matrix and replacing individual 7-Segment displays with a common anode 4 digit 7-Segments module a simple ...
RTC Real Time Clock PCF8573P Featured Image

PCF8573P I2C Real Time Clock

In this post I’m going to show you how to interface an I2C Real Time Clock – RTC with PIC microcontroller. Only a basic hardware configuration and a communication protocol are presented here. I’m planning to extend it to a ...
BCD to 7 Segment Display Decoder Featured Image

BCD to 7 Segment Display Decoder

In this post I'll show how you can drive 7 Segment LED display with PIC16F876A. Instead of using a dedicated IC’s like 4511 we’ll program the micro controller to convert  BCD input code 0 – 9 to a 7 Segment LED ...
Digital Stopwatch Featured Image

Digital Stopwatch

Source code for this circuit was not written from scratch, instead a number of functions were taken from previous designs like multiplexing routine for 7-Segments displays, I2C communication. Current code may be not the most efficient implementation of Stopwatch design ...
Basic PIC Frequency Counter Featured Image

Basic PIC Frequency Counter

Here is a Basic PIC Frequency Counter design. For Arduino version click here. It doesn't not attempt to compete with some advance designs and has a very limited frequency range, however it can be used as a starting point to ...