I commented out a few lines in ahc_pci.c and found that
I can force my disk to 20mhz.  It appears to work, but of
course is just a vulgar hack.  If anyone is interested
in what I did, email me.

Thanks,
Nick Maniscalco 
nmanisca@vt.edu

At 10:15 AM 8/29/98 -0400, you wrote:
>At 02:00 AM 8/29/98 -0700, Todd Whitesel wrote:
>>> This 3rd disk is ultra wide (20mhz 16-bit xfers)
>>> 
>>> Now, I put the 3rd disk at the end of the wide scsi cable coming out
>>> of the adaptec and the boot up messages say that its using 10mhz xfers :(
>>> 
>>> So can you not mix fast and ultra devices on a single cable without
>>> falling down to the slowest device?
>>
>>Can you put the wide disk on a cable by itself and boot an installation
>>floppy to see what xfer speed it gets?
>
>Good idea, I will try this.
>
>>I have a couple ultra-wide drives myself, and they always seem to come up at
>>10 mhz. I have non-ultra devices on the same bus now, but I vaguely recall
>>booting without them long ago and still getting 10 mhz transfers.
>>
>>Looking at /usr/src/sys/dev/ic/aic7xxx.c, I see that 10 mhz is the highest
>>"non ultra" transfer frequency. So maybe something is globally disabling
>>ultra features in the driver?
>>
>>Todd Whitesel
>>toddpw @ best.com
>
>Think it would be possible to force the driver to talk 20mhz to a 
>ceartain device?
>
>Thanks,
>Nick
>
>
>