Z-Turn GPIO add-on

This board brings out the GPIO pins found on the CN2 connector and routes them through 74LVCH245 buffers out to normally-sized pin headers.

The board features two ways of powering the buffers, selectable by J1 jumper pins:

EXT 3.3V - uses the 1117 linear regulator on the PCB, which is connected to the Z-turn's 5V supply
INT 3.3V - uses 3.3V supplied by the Z-turn board

Of course you can connect your own supply to one of the VCC pins if you want to (after removing the jumper).

The board features five 8-bit bi-directinal buffers - 74LVCH245. The direction can be set individually for each buffer.