Basic frequency counter capable of measuring 0-5V square wave up to 100kHz can be built using just 2 components: Arduino MEGA board and 2x16 LCD display. For PIC16F876 version click here. Frequency counter code is also very simple. It uses ...

Following recently published article about building a PWM Fan Controller here is another simple controller design. This time it’s a 2 Channel PC Fan Controller for standard 12V Fans. It uses software implementation of PWM but instead of directly driving PWM ...

Arduino based 3 Digit Timer with LED Display module is a relatively simple design. Recently I’ve published a number of similar projects that essentially perform the same task. You set up an initial value via some kind of user interface ...

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 ...

Here is a modified and improved electronic lock design. For Arduino version click here.It is largely based on Digital Lock article, however this time a real electronic lock was used instead of a solenoid. The code is a 4 digit number ...

Solar power mobile charger can be built by tweaking digital power supply schematic. The Software/Hardware stayed almost the same as the original circuit.Current design has the same overcurrent protection and output voltage can be changed by pressing SW1. Voltage and Current ...

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 ...

MAX7219 is a serial input/output common-cathode display driver. It can interface the microcontroller to 7-segment numeric LED displays, bar-graph displays, dot matrix display or  individual LEDs. This IC has some very useful features like built in decoder, multiplex scan circuitry, ...

In this post a basic character generator design based on PIC16F88 will be demonstrated. 7x5 Dot Matrix Display was used and its pin out is shown in the schematic below. Instead of using PIC16F876/7 microcontrollers PIC16F88 was chosen for this purpose ...

A few weeks ago I’ve uploaded post with relatively simple assembly code example for interfacing 2x16 LCD display with PIC16F microcontrollers. Driving Graphic LCD display is more complex task  as it lacks the build in character generation unit so each pixel needs to ...