Compact speedometer with OLED display and temperature measurement.
It features an ATtiny85 uC with USB programming and battery charging and protection circuitry. I will be using it to measure the speed of my bicycle and determine the temperature around me on my rides.
The project consists of 2 pcbs: the sensor that will be mounted on the wheel of my bike and the actual speedometer.
Programmable Signal Generator
This project describes a simple digital signal generator capable of generating a square wave from 1kHz to 68MHz with an accuracy of 1.1%. You enter the frequency on a numeric keypad, and the frequency is displayed on an I2C 128x32 OLED display.
Used components: ATtiny85, OpAmp INA331/LTC6904, OLED display (connector JP1/JP3).
This is the code I use for the clock. Feel free to change it in each manner your want. ATTENTION: Dont use the POV Clock_old. I use it for backup purpose only. It wont work! The file POV Clock_new and POV_Clock_new_SSD1306 are working well and are fully tested. But i dont take any responability if something dont work like you want. For example: the optocoupler is tricky. Maybe you need to adjust t...
This small device that indicates an input byte in hexadecimal on two 7 segments led displays. It can be inserted into a breadboard or a connector. It displays in hexadecimal the byte placed on its 8 binary inputs.
It is powered in 5 volts and consumes only 10 to 15 milliamperes because thanks to multiplexing, at most only one of the 14 segments is switched on at a time.
It can replace 2 TIL...