From: Gideon Zweijtzer (gideonz_at_dds.nl)
Date: 2003-07-06 18:40:44
Spiro wrote: > In fact, I really doubt a breaking charrom would influence > the displaying of sprites without affecting the 6510 in any > way - the only way I see the charrom could influence the > sprites is in that it "shortens" some data or address bus > pins, but in this case, even the 6510 would not be able to > see anything useful. > > What I see as possible candidates (the list is not complete, > there might be other things, too): > > - the VIC-II itself > - the PLA > - the CIA#2 (which generates the address bus lines A14 and > A15 for the VIC). I think the CIA#2 is not a candidate, because changing the address lines A14 and A15 to the VIC-II does not cause sprites to appear, as they are being turned off in the startup routine of the C-64. It is more likely that some writes to memory also reflect in writing registers of the VIC-II, and hence I think it is the PLA. Gideon Message was sent through the cbm-hackers mailing list
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