Hello Steve, > I think most computer monitors have a tolerance to slightly varying > frequencies so I'm not so concerned about getting exact timing. That's true. But if you and the monitor use the tolerance in different directions ... ;-) > Of course I can make an edit rom with values for PAL timing but it > would be nice to have them verified with real hardware. At this time i'm to busy to test it. > What if any other side effects would there be in changing the main > crystal to 16.128? The CPU is running less than 1 percent faster! All other timings based on Phi2 (VIA timer) are changed, too. > Would the pet run at 18 MHz (like the CBM-II machines)? No, the CBM-II machines divied the clock by 9. The width of characters are 9 pixel! But the CPU runs with 2 MHz, so the charcter clock of the CRTC is 2 MHz (instead 1 MHz), too. So the horizontal frequency is 15,748 kHz, very near to the real 15,750 kHz. So it's a normal 18 MHz crystal used. Martin Message was sent through the cbm-hackers mailing listReceived on 2013-04-12 19:00:03
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