From: Jim Brain (brain_at_jbrain.com)
Date: 2007-05-09 08:56:20
Daniel O'Shea wrote: > I was wondering, in both Jim and Levente's microcontroller to joystick > port projects - is interfacing a microcontroller's digital output > (high/low) to the joystick input likely to cause the same issues with > the CIA chip as noted here: > > http://www.floodgap.com/retrobits/ckb/display.cgi?26 > > Message was sent through the cbm-hackers mailing list I doubt either of our projects has this issue. In mine, for example, IO is done thusly: output to joy DDR logic level notes HI input high internal pullup engaged LO output lo tied directly to ground (well, close to it) LO->HI: switch DDR to input, then switch logic level to high to engage pullup. Doing it this way ensures you never drive pin with 5v directly HI->LO: disengage pullup, then switch DDR to output. Jim -- Jim Brain, Brain Innovations (X) email@example.com Dabbling in WWW, Embedded Systems, Old CBM computers, and Good Times! Home: http://www.jbrain.com Message was sent through the cbm-hackers mailing list
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