First i must say the retropie project is brilliant and having a right good time getting it all set up. However whilst im quite good with Linux, (Get to play with headless servers at work) my electronics skills are somewhat lacking.
So ive got my NES controller wired up like so (using model B+ board):
power Pin 1
gnd Pin 6
data Pin 5
clock Pin 19
And im using snesDev as the driver however in jstest it recognises i have two controllers but doesn’t show any activity on the controller. So i briefly ran it on 5v and boom jstest shows life.
Ive read that there are three types of NES controllers:
1: Completely 3.3v compliant
2: Needs a 5v power source (Data out will have to be brought down to 3.3v) But clock and latch lines can run on 3.3v
3: Completely 5v dependant
So going of above my controller must fall into category 2. So i thought no problem simple voltage divider on the data-out line and boom.
Whilst playing with the multimeter and my mock-up divider i hit up the data, clock and latch pins out of curiosity and here is where im confused.
When running on 3.3v all lines are at 3.3v, however when running at 5v all lines, including the latch and clock are at 5v? How is this possible? I thought the latch and clock lines are sent from the rpi and so at 3.3v? Can anyone explain what is going on here? I do have to admit its also possible im using my multimeter wrong.
Ive used the usb alternative controllers and they just feel awful compared to an original, but i dont want to damage my pi either.