What is it?

It is a GPIO reference board for Raspberry Pi. It has LED on each GPIO pin to show the state of the GPIO. Every GPIO pin has a description, so you can easily find the proper pin.

Why did you make it?

Every time I was using GPIO on Raspberry Pi I had to print GPIO pinout. I thought it will be very useful to prepare PCB labelled with GPIO names and LEDs to show the state of the PIN.

What makes it special?

LEDs do not interfere with GPIO pin. LEDs are connected thru buffers, so they do not drive current from pins. LEDs and buffers have their own LDO connected to 5V rail.

This board size is 57x33mm. Its fully assembled (except included Stacking Header) and tested.

Now, you can bought only a PCB and test yours skills in SMD soldering!