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Revision 1 CPU DMA crash: Difference between revisions
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=== References === | === References === | ||
# [https://archive.org/details/SNESDevManual/book1/page/n111 page 2-25-1 of Book I] of the official Super Nintendo development manual | |||
# https://forums.nesdev.org/viewtopic.php?t=13280 | |||
[[Category:SNES Hardware]] | [[Category:SNES Hardware]] | ||
Revision as of 20:16, 13 July 2023
Little is known about why the CPU revision 1 DMA crash happens. In 2015, Ramsis wrote a test rom to trigger it. [2]
Trigger
- kicking of an HDMA at about the same time that a General Purpose DMA finishes
Symptoms
Workarounds
- Use GPDMA only during vblank
- Make sure HDMA starts in the middle of a GPDMA data transfer
- Avoid HDMA
- Adjust the time at which GPDMA begins
- Decrease the number of bytes transferred during GPDMA
References
- page 2-25-1 of Book I of the official Super Nintendo development manual
- https://forums.nesdev.org/viewtopic.php?t=13280