Subject: Re: port-i386/2109: ultra14f.c byte-read of board ID fails on 34f (mine at least)
To: Mark H. Weaver <mhw@NETRIS.org>
From: None <Chris_G_Demetriou@NIAGARA.NECTAR.CS.CMU.EDU>
Date: 02/23/1996 11:22:25
> Chris_G_Demetriou@NIAGARA.NECTAR.CS.CMU.EDU writes:
> > >
> > > Recent changes to ultra14f.c cause it to read the board ID and
> > > configuration using byte-reads instead of word-reads, perhaps because
> > > this was necessary for someone else. On my 34f (VLB), the byte-reads
> > > don't yield a valid board ID, and the board is not recognized.
> > What _is_ returned by byte reads?
> Sorry, should've thought to check for that. 0x4156 is read, and
> 0x5641 is what we want, meaning that the word-read seems to be
> returning the big-endian representation for some reason.
That's what I expected. I've seen other hardware do this, too. (EISA
ID registers...) Perhaps this is why my 53c825 boards all have an
endianness jumper, which has mips & alpha as on 'endianness,' and PCs
as a _different_ one...
> Was the change to byte-reads ever tested?
I dunno, but looking at your problems, i'd be willing to guess... 8-)