Posted by Andy Warne on 16, 2001 at 4:49 PM:
In Reply to: K64 vs IPac: responsivity posted by Ray on 15, 2001 at 9:08 PM:
The I-PAC doesnt use polling. Each input has it's own chip pin on the microcontroller and when pressed the button generates an interrupt and sends the code, done.
As Ron says, there is also the issue of switch bounce so a state counter is used for each input which prevents that input from sending a second code if a break follows a make within a very short time.
If you're using Windows though, the delay introduced by any interface (even a hacked keyboard) would be dwarfed by the delays in the Windows keyboard drivers. Then MAME has delays as well. Advanced MAME has quite long and variable delays in the keyboard routines. Maybe that's part of sync'ing with the video rate.
Andy
: Folks
: Has anyone directly compared the responsivity of the K64 encoder and the I-Pac controller?
: I-Pac looks to have a tighter polling loop, but K64 seems to have some intelligent polling.
: Basically, is there a different noticable on highly timing sensitive games (fighting games, etc.)?
: Just curious how noticable different polling techniques are.
: Ray