I'm using an Arduino Mega to receive data and control many devices. 16 of the DIO lines are for input and the other 16 lines are for output. the 8 analog lines supply the 7 bit address and strobe lines. a 688 is used to decode the address and the 573 D latches serve as the IO gates. In output mode OE is wired to to GND (high impedance is not used) the output from the 688 and the strobe line are mixed in a 74HCT00 to toggle the LE line and upload new data to a specific output board. That worked fine. For input the LE line is wired to VCC, keeping the 573 in a transparent state and the address and strobe through the 74HCT00 are used to toggle the OE line so only one input board should be on line at any moment.
However the 573 chips are locked in the high impedance state and no data is being transferred to the outputs. Has anyone run into this or have a suggestion on how to fix it?