Here's my spreadsheet with all the timings from all common ROM's I could find plus the others that are on zimmers. You can use this to twiddle with the values and see the effect on the frequencies. http://inchocks.co.uk/commodore/PET/PET_CRTC.xls Anders is correct for the 80 column edit roms. For the 40 column ROM's the registers are at E7B1 and E7C3. Rob On 19/12/2013 13:21, Anders Carlsson wrote: > Hervé wrote: > >> - What are registers values supposed to be OK ? > > Perhaps André:s site can help you? > http://www.6502.org/users/andre/hwinfo/crtc/ > http://www.6502.org/users/andre/petindex/crtc.html > > It seems to that changing the register R2 would move the image to > either left or right. The second page has actual register values, see > the ones for CS/A65 as those were tuned for a 50 Hz TV. André also has > links to the composite video adapters and mentions that the CRTC > values need to be changed in order to get them to work. > >> - Locations, in this hacked ROM, to patch to change those registers >> values ? > > A quick hunt with the xpet monitor suggests $E72A (lower case?) and > $E73C (upper case/graphics?), but I'm not entirely sure. > > Best regards > > Anders Carlsson > > > Message was sent through the cbm-hackers mailing list Message was sent through the cbm-hackers mailing listReceived on 2013-12-19 17:00:05
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