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Old 14 March 2016, 11:15   #23
phx
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Join Date: Nov 2009
Location: Herford / Germany
Posts: 2,525
Quote:
Originally Posted by Lazycow View Post
Instead I used the copper and just disabled sprite-DMA with
dc.l $00960020
...and moved the sprites into the horizontal blank.
When you disable DMA, then no more new data is fetched into SPRxDAT. But the sprite is still armed and writes its last data every line, as DanScott already mentioned.

Usually you have a similar situation when you take over the system and disable all DMA. Sloppy coders forget to disarm the mouse pointer sprite, which sometimes shows as a long vertical bar over the screen. In this case you either have to write zeros to SPRxDATA/SPRxDATB or disarm the sprite with writing 0 to SPRxCTL.

Quote:
Originally Posted by Lazycow View Post
ok, let's hope the best. Another thing: Will it speed up the CPU when I disable sprite-DMA? I know that 5 or 6 plane bitmap DMA will slow down the CPU, but sprites?
No, I don't think so. Sprite, Disk and Audio DMA slots are fixed. Nobody else can use them (ok, except the last sprite DMA slots may be overridden by bitplane DMA).
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