Re: What to do with slow Chip/ST RAM

[mlelstv%serpens.de@localhost (Michael van Elst)]

is%NetBSD.org@localhost (Ignatios Souvatzis) writes:

>Uhm... what's exactly the purpose, again? If it is for prioritized
>used of main system RAM, I think ZII RAM (at least) isn't accessible
>to (at least some of) the SCSI DMA drivers.

Au contraire. Z-II RAM is, Z-III RAM and other 32bit RAM on accelerator
boards isn't. But this depends on the SCSI controller, in particular
if it is itself sitting on the Z-II bus.

That's why AmigaOS (finally) also kept track of MEMF_24BITDMA.

All this is pretty academic though. Most people will have an
accelerator with local RAM and local SCSI controller, or an
A3000 with a SCSI controller that has no such limitation, or
an IDE adapter run in PIO mode.

-- 
-- 
                                Michael van Elst
Internet: mlelstv%serpens.de@localhost
                                "A potential Snark may lurk in every tree."