In this post we’ll review a simple interface for PCF8574 I2C 8-bit IO expander IC and PIC microcontroller. For similar Arduino based implementation click this link. The format of present post is similar to 2 recently published tutorials about I2C ...

Pulse Width Modulation (PWM) is very common technique for controlling cooling fan speed in Desktop PC. In this project PIC16F877A based Pulse Width Modulation  controller was built and tested with 2 fans. 80 mm Coolink SWiF2-80P PWM Fan and Arctic Cooling ...

Raspberry Pi I/O capabilities can be expanded by adding one or cascading a number of shift registers. In this design 74HC595 example is shown. 74HC595 is a very popular and relatively cheap IC. There are assembled modules based on this ...

Simple digital voltmeter can be built by using PIC microcontroller and a few discrete components. PIC16F877A 10 bit ADC module was used for this purpose, we’ll work only with 8 upper bits to translate input voltage to digital form and ...

Arduino based LCD Bargraph Voltmeter can be easily assembled with Arduino Mega 2560/Arduino Uno or compatible boards. Arduino LED battery level indicator is here. Similar design based on Raspberry Pi platform is available at this link. This design is basically ...

In this short tutorial we’ll learn how to control PCF8591 I2C 8-bit A/D and D/A converter with PIC microcontroller. PCF8591 was already used in a number of recently published projects like Function Generator, also I’m planning to add it to ...

A simple light sensor can be built using a photoresistor and Arduino UNO board. Similar design is available here. This design requires only a few additional components like 10k resistor and a 10k potentiometer to adjust the light intensity level ...

Due to popular demand I've modified digital clock design to work with LCD display instead of 7-Segment LED as described in this post. For Arduino version click here. All the capabilities of LED version have been maintained in current project. 1 ...

9 Volt batteries extensively used in various electronics measurement equipment. Powering these devices with  rechargeable batteries can be a cost effective solution. In this post a simple Lithium-ion 9 Volt Battery Charger design with overcharging protection will be presented. Charger is ...

For this project two PIC16F877 MCU's were used, see project schematics below. Slave PIC runs  LEDs decoding and multiplexing code on data received from Master. 7-Segment inputs connected to PORTC,B and common digits anodes to PORTB,A via 2N3906 collectors for ...