$2004 Reads

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$2004 Reads
by Muchaserres on 2007-07-18 (#25907)
http://nesdev.com/bbs/viewtopic.php?t=2295

Has anyone got on their emu the real values following "Sprite evaluation" at the wiki?

I've got all tests passed, but read2004.nes is kind of hard to emulate accurately. I get exact values for range 256-319 if I modify wiki steps like this,

1-4: Read the Y-coordinate, tile num, attributes, and X of selected sprite +1.
5-8: Read the X-coord of selected sprite +1 4 times.

Has anyone got similar trouble?

Thx.

M.

by mattmatteh on 2007-07-19 (#25909)
i got the test to pass and tried for a little while to get the output right like quietust did, but failed. meanwhile i am working on re doing my ppu core. right now its pixel catch up which is just plain toooo slow.

matt

by Muchaserres on 2007-07-26 (#25984)
Got it to work properly except for the last four values. Those should be all 0x00 but I get 0xFF. They don't seem to map into $2004 reads though.. I'll have to investigate that. Any suggestions?