On Thu, Jun 06, 2002 at 08:27:51AM -0400, Michael R. Zucca wrote:
> I think this is the case. Eventually, it might be nice to write our own IOP
> code for the case where we boot directly since the IOP code that comes from
> the ROMs might have bugs.

Not only that, but the IOP code from the ROMs is written for MacOS, not
for *nix.  A/UX, I believe, loaded their own code.

> However, for those that don't know, the protocol to speak to the IOPs is
> well understood. There's a working driver in Linux and Allen tried to make
> a port of the code to NetBSD.

It's at least mostly understood.  As you say, I have code that should
work, but doesn't for some reason, and I haven't had the time to go
back and look at it.  Amazing what work, house, marriage, and kids do
to a hacking schedule...  ;-)

> I don't think the 6502's get reset on NetBSD boot, but I'll bet there's a
> way to reset them so they load a new "kernel".

The IOPs are 6502 cores, I think, but possibly modified/specialized
somewhat.  Kind of like the VIAs, SCCs, etc., ISTR that Apple licensed
the logic core and slapped it onto an ASIC.

-allen

-- 
 Allen Briggs                     briggs@wasabisystems.com
 http://www.wasabisystems.com/    Quality NetBSD CDs, Sales, Support, Service
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