I want to simultaneously trigger 4 DAQ nodes from a 5th control node (each node is a Raspberry Pi) see below. I have a number of solutions in mind with issues for each,
Naïve solution, just connect the GPIO pins in parallel to the control GPIO pin, they all share the same ground, will their be fan out issues?
Buffer each parallel connection to mitigate fan out, is there something missing here?
Use a 4-bit Universal Shift Register eg 74LS194 with the parallel input register all 1s & clock this via the control node, is this overkill or is there another reason this shouldn't be done?