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Old 25 May 2019, 10:48   #50
Defendit numerus

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Join Date: Mar 2017
Location: Crossing the Rubicon
Age: 50
Posts: 3,213
Originally Posted by Toni Wilen View Post
I don't think it works with DMACON because I am quite sure RW head is still being driven (floppy write gate signal is active). I assume it is bit 14 that controls it + DSKLEN being in "active" state.
Yes you are certainly right.
Have you ever found any code that you use directly DSKDAT ($26)?.

But I guess you could stop writing temporarily by clearing bit 14 of DSKLEN (but keeping bit 15 set), if bit 15 is kept set, new DSKLEN value gets loaded in internal disk length counter without interrupting active disk DMA. EDIT: But switching read<>write on the fly probably causes other side-effects because afaik read and write uses different Paula internal fifo logic.
Maybe in the past someone tried it and failed? Who know..
Anyways are just free thoughts on a Saturday morning
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