Say Merry Christmas with LED display

Would you like to say “Merry Christmas” to everyone that passes by? Then hang a big LED message display. The display message is divided in to 9 distinct letters controlled by PIC16F688 via transistors. The fun begins when programming starts. Here you can drive message by sending different letter lighting patterns like switching letters sequentially, blinking whole text or simply displaying whole message. Fix it on your house and have your attention. Continue reading

Simple and secure DIY digital voltmeter

Sometimes in your projects you may need simple voltage tester that would require few parts and would be reliable at some level. If you have MCU with ADC in – consider half job done. The only thing left is to align voltage input circuit. In this case there is a small PIC16F688 microcontroller used with DAC. The only problem is that microcontroller can accept 0-5V. To do 0-20V there is a voltage divider used with 5.1V zener diode protection in case voltage goes higher. IMG Voltage value is displayed on 2x16LCD screen. So why not to put this thing in your car to monitor battery charging status? – I did 🙂 Continue reading