TG-16 controller I just dug out of the mess of untested controllers I sometimes pick up from Goodwill, Salvation Army, various sales, and even in rubbish bin. It's acting odd. When I press U, D, L, or R, nothing happens.
Using controller test ROM (via Everdrive), it confirmed nothing working on the control pad. HOWEVER if I pressed Start, Select, I, or II button, it also triggers direction. Examining the schematic, the common issue seems to be data toggle line to pin 1 of 74HC157 is not toggling and stuck in high. I checked the wire and PCB trace, there is continuity from the plug all the way to pin 1
Using a logic probe, I am getting pulse on pin 1 so the signal is getting through.
Does it mean the chip is partially bad? The 4 buttons still work but directional does not work. Or is there something else I need to check first?
Topic: Controller doesn't work right, no U, D, R, or L (Read 216 times)
