Re: The TF536 on a CDTV
Posted: Sun Jun 16, 2019 6:43 pm
Nope...TF534 & TF520 producing green screen on my cdtv...
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ROM:000003E0 ; =============== S U B R O U T I N E ======================================= ROM:000003E0 ROM:000003E0 ROM:000003E0 sub_3E0: ; CODE XREF: ROM:00000146↑p ROM:000003E0 ; ROM:000001A0↑p ... ROM:000003E0 moveq #0,d1 ROM:000003E2 move.l a6,-(sp) ROM:000003E4 movea.l (unk_4).w,a6 ROM:000003E8 jsr -$C6(a6) ROM:000003EC movea.l (sp)+,a6 ROM:000003EE tst.l d0 ROM:000003F0 rts ROM:000003F0 ; End of function sub_3E0 ROM:000003F0
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ROM:00F0407C word_F0407C: dc.w $7200
I guess we can find out by testing a CDTV in WinUAE with that as a breakpoint.
Patching a single ROM location is easy but i have a suspicion that this rom is mirrored in a few places. we'll need to check its not executed at 0xE0xxxx or $A8xxxxCan You redirect it on the fly? We can also patch cdtv.device in extended rom in worst case...
CDTV + accelerator can have multiple problems:
- CDTV CD drive is DMA capable and can't access any RAM outside of first 16M address space (24-bit Z2 limit)
- CDTV CD autoconfig board must be located at $e90000 (=must be first 64k Z2 IO device in autoconfig chain. It is autoconfig but ROM driver uses hardcoded addresses..). Accelerator may have its own 64k IO board which will conflict with CD device. Simple workaround is to make sure accelerator Z2 IO (If it even has one) is at least 128k in size.
- Even if accelerator has only "24-bit" RAM (max 8M), it most likely don't have any external DMA support.