Hey, big guy. #retrocomputing #tms9900 #m68k #x86

It sure does look good, but it doesn't work. And I believe bad breadboards are the problem. :-( The displayed voltage is the ground pin on an arbitrarily chosen logic chip, with reference to the primary power rail very close to the input supply.

I see ground return resistance voltage lifts of between 0.1 and 0.7 V on many chips on this board. I'm increasingly confident that is the reason that this board does not boot and displays unreliable behavior.

#retrocomputing #homebrew #tms9900