Heathkit H-11 restoration questions

From: CLASSICCMP_at_trailing-edge.com <(CLASSICCMP_at_trailing-edge.com)>
Date: Mon Oct 4 12:03:24 1999

>The card itself is about as simple as any Qbus card. It is, I take it,
>supposed to be nominally RXV11 compatible from a driver standpoint, yes?
>If not, then that's part of my problem. I do boot, the disks to appear to
>read in an OS, then the system hangs, but that could be as a result of my
>card only working if it is *not* at the end of an unbroken grant chain (with
>a gap in the bus, the disks read but the system does not boot; without a gap
>in the bus, the CPU does not even bring up the boot message).

The RXV11 doesn't do DMA, and while booting it may not need
interrupts. But after the OS is bootstrapped and is "going" it'll
probably start looking for interrupts.

The fact that the machine hangs solid when the card is where it's
supposed to be may be a clue that the it's permanently stuck interrupting.

Does the Heath machine at least have a "halt" button so you can
get down to console ODT ("_at_" prompt) and do further debugging from there?

-- 
 Tim Shoppa                        Email: shoppa_at_trailing-edge.com
 Trailing Edge Technology          WWW:   http://www.trailing-edge.com/
 7328 Bradley Blvd		   Voice: 301-767-5917
 Bethesda, MD, USA 20817           Fax:   301-767-5927
Received on Mon Oct 04 1999 - 12:03:24 BST

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