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Old 21 December 2012, 00:03   #1
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Join Date: Aug 2004
Posts: 2,831
CIA-A TOD clock source with genlock

The A500/A2000 Technical Reference Manual mentions (on page 9):
In the A500, the Time of Day clock is tied to the VSYNC signal rather than the power line. This results in the theoretical error of several minutes a day. For more precise timing, use the optional real-time clock.

In genlock mode, the genlock peripheral provides a 30Hz V/Z signal, which results in the clock running at half speed.
I assume the Z is actually a misprint for 2. Does WinUAE emulate that feature when CIA TOD source is set to vertical sync and the genlock connected box is checked? Seems a bit weird to me, though I never used a genlock back in the day.
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