tonioni / WinUAE

WinUAE Amiga emulator
http://www.winuae.net/
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A4091 improvements #227

Open reinauer opened 1 year ago

reinauer commented 1 year ago
tonioni commented 1 year ago

Is this different hardware than 32k ROM or does all A4091 variants support 64k ROM and if 32k ROM is installed, it appears twice in address space? (I have A4091 but it does not work..) Is this ROM Commodore official one or some 3rd party modification?

Also generic 53c710 code shouldn't be modified but A4091 specific part because other boards also use it and might (accidentally) hit out of range addresses that shouldn't hit SCSI chip IO. You never know :)

reinauer commented 1 year ago

64K ROMs are supported by all DKB (Rev B) versions of the A4091. I think your assumption about 32K ROMs being mapped twice is correct on those boards, but I did not verify.

The ROM I've been using is a (soon-to-be open-sourced) rewrite based on the NetBSD driver that supports NSD and TD64 as well as other improvements. This is work that was done for the ReAmiga 4091 project. Yes, I know it is not an "official" driver, but with the above changes WinUAE was particularly useful during development of the driver.

If you're generally interested in merging, I can move the register wrapping out of the 710 specific code.

tonioni commented 1 year ago

A4091 64k ROM support should now be transparent (32k gets duplicated). Address masking is also now device specific.