I have a basic idea of how this could work. since clocks make things faster, lets implement that.

SERIAL INITIALIZATION

Pins set accordingly. Outputs set high. Serial port waits for a low on their inputs of a certain duration (will figure this out later). The input becomes the DATA_IN and the output becomes CLK_OUT

SERIAL TRANSMISSION

Transmitting micro sends a low pulse on the output and waits for a clock signal from the receiver. the clock's rising edge updates the data output and the falling edge latches the data.

This should work! I'll update the project after some code and testing.