jgreco@csd4.csd.uwm.edu (Joe Greco) (10/01/89)
Hello.... I have been experimenting with a 6522 VIA chip. I'd like to map one into the 64's I/O space, but I ran into a little trouble. It doesn't work.... I have simply connected all CPU-side pins on the VIA to their expansion port counterparts, except for CS1. (CS2* is connected to IO1). It doesn't work, but if I disconnect CS1 amd put a 6526 CIA in place, it works perfectly fine. Does anybody know of any timing problems or other possible causes? Thanks.... - Joe -- jgreco@csd4.milw.wisc.edu Joe Greco at FidoNet 1:154/200 USnail: 9905 W Montana Ave PunterNet Node 30 or 31 West Allis, WI 53227-3329 "These aren't anybody's opinions." Voice: 414/321-6184 Data: 414/321-9287 (Happy Hacker's BBS)
po87553@tut.fi (Ojala Pasi Juhani) (10/02/89)
In article <284@uwm.edu> jgreco@csd4.csd.uwm.edu (Joe Greco) writes: > >I have simply connected all CPU-side pins on the VIA to their expansion port >counterparts, except for CS1. (CS2* is connected to IO1). It doesn't work, Hmm, my friend made the opposite to his vic, and his CIA is working fine. Hey.. Cs1 is active high, so you better connect it to Vcc and /Cs2 to /IOx.. -- ++++++++++++++++++++++++++++++++++++++++++++++++++++ + Pasi Ojala The smaller .signature you have+ +po87553@alva.UUCP the more frieds you get. + ++++++++++++++++++++++++++++++++++++++++++++++++++++
jgreco@csd4.csd.uwm.edu (Joe Greco) (10/03/89)
In comp.sys.cbm article <2119@alva.tut.fi>, po87553@alva.UUCP (Ojala Pasi Juhani) wrote: > Hmm, my friend made the opposite to his vic, and his CIA is working fine. >Hey.. Cs1 is active high, so you better connect it to Vcc and /Cs2 to >/IOx.. Trust me, it was the first thing I thought of. I had it connected correctly, but also tried grounding it in case my docs were wrong. Perhaps it's just that both of these stupid VIA's are bad...? -- jgreco@csd4.csd.uwm.edu Joe Greco at FidoNet 1:154/200 USnail: 9905 W Montana Ave PunterNet Node 30 or 31 West Allis, WI 53227-3329 "These aren't anybody's opinions." Voice: 414/321-6184 Data: 414/321-9287 (Happy Hacker's BBS)