Hey guys,
I just need some general information about how the NES communicates with the standard controllers.
Are the gamepads polled in most games (i.e. within the gameloop) or do they generate an interrupt to the CPU (like the V-blanking period)?
I have been looking at various spec sheets, and they explain that the data from the gamepads can be read from by strobing addresses $4016 and $4017. It would seem that doing this, they could be read from at any time, suggesting that they are polled. However, this would make periodic communication between the gamepads and the CPU very unlikely.
I just need some general information about how the NES communicates with the standard controllers.
Are the gamepads polled in most games (i.e. within the gameloop) or do they generate an interrupt to the CPU (like the V-blanking period)?
I have been looking at various spec sheets, and they explain that the data from the gamepads can be read from by strobing addresses $4016 and $4017. It would seem that doing this, they could be read from at any time, suggesting that they are polled. However, this would make periodic communication between the gamepads and the CPU very unlikely.