screen rendering

Discuss emulation of the Nintendo Entertainment System and Famicom.

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Zepper
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screen rendering

Post by Zepper »

- What is the cycle that the first pixel is rendered, but not plotted? I know it's during the HBlank period, but what cycle?
Nessie
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Post by Nessie »

Do you mean when the tiles are prefetched for the next scanline?
That's during cycle 320 through 335 (if you start counting from 0).

Search for "Memory fetch phase 161 thru 168" here:
http://nesdev.com/2C02%20technical%20reference.TXT
A "memory fetch phase" is two cycles, so fetch phase 161 means cycle 320 (brad taylor's doc starts counting from 1).
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