No you can’t just remove the Q777 – From memory there is some logic that is required to enable DMA operations to continue as normal.
At minimum If I remember correctly you need a Q007 to place in that slot instead. This was a card with may be 1 or 2 LS logic chips on it that completed the DMA chain.
There are a few references to the Q007 here … http://kmi9000.tripod.com/kmi_cmi_hard.htm
From: Fairlight-CMI@yahoogroups.com [mailto:Fairlight-CMI@yahoogroups.com]
Sent: Tuesday, July 14, 2015 08:33
To: Fairlight-CMI@yahoogroups.com
Subject: [Fairlight-CMI] Can a Q777 be removed from a Rev11 / 9.34 Series III?
Hi all,
Not much activity on the forum these days, so hoping that a few are still hanging around!!
I'm going through a full service of my Series III at the moment and in the interests of log-term reliability and power consumption, I'm removing all cards and devices that are not necessay to it's day-to-day operation (such as the floppy contoller and drive).
With this in mind, does anyone know if it is possible to remove the Q777 card? To be honest, whilst I'm aware that for the earlier revisions it held the SCSI device firmware, I'm not sure what it's role is in a latter spec Series III, given that the CMI41 and TS-1 are handing SCSI activities. All I know is that the machine won't work without it!
Any advice would be welcome.