Subject: Re: Question about the ESP100 NCR SCSI chip in Sun machines.
To: Brian Buhrow <>
From: David Brownlee <>
List: port-sparc
Date: 07/18/1997 11:35:16
	IIRC the ESP100 has problems with noice on synchronous transfers -
	Under SunOS 4 you could use adb to patch a variable that would
	turn synchronous on, which worked fine for me on a machine with
	internal drive sonly..


    "Its a bright sunny california day outside, and you're inside."
    "And your point would be...?"

On Fri, 18 Jul 1997, Brian Buhrow wrote:

> 	Hello.  I note that in sys/arch/sparc/dev/esp.c, as distributed in
> -current sources, on the 1.2.1 source tree, and on the 1.2 source tree, the
> ESP100 chip causes the driver to disable synchronous SCSI transfers.  Is
> this inability to do synchronous SCSI transfers with the ESP100 chip a
> peculiarity with our driver or synchronous transfers silently disabled on
> the SunOS 4 and SunOS 5 drivers as well?
> 	If the chip is incapable of actually doing synchronous transfers, how
> hard would it be to put a newer revision of the chip on a Sparc 1 mother
> board?  If it is capable of doing transfers synchronously, how hard would
> it be to teach our driver to cope with its idiosyncracies?
> -thanks for any enlightenement.
> -Brian