Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!uwm.edu!zaphod.mps.ohio-state.edu!uakari!ames!uhccux!munnari.oz.au!murdu!ucsvc!ltu!ccpn
From: CCPN@latvax8.lat.oz (Paul Nankervis)
Newsgroups: comp.sys.dec.micro
Subject: Re: Rainbow boot error
Message-ID: <361@latvax8.lat.oz>
Date: 26 Feb 90 21:05:55 GMT
Organization: VAX Cluster, Computer Centre, La Trobe University
Lines: 21

>  How often does it appear?  Have you turned off/on the Rainbow, let
>  it sit off, and then test boot it again?  Does it ever boot up all
>  the way?  It it ever boots up, do you have any diagnostic software
>  that you can run?

Whatever it is the error is hard on. I tried the board in a 100A to test power
supply, cables and RX50 controller but I still have the problem. I have swapped
the Z80 chip and checked for any obvious board defects. I was thinking that
there may be a RAM problem when I realised that there is a separate message to
cover that. It must be either the unshared RAM (unlikely as it is static RAM),
access to the shared RAM, or the ROM code copied into shared RAM is corrupt
(when copied from ROM). I was wondering if anyone has access to the PC100
firmware code and could tell me what is happenning when the error occurs (all
lights on except 5 & 6). I may try borrowing a set of ROMs from somewhere to
see if that is the problem. 
It would be great to have this system up and going again.

Thanks in advance
Paul Nankervis
La Trobe University, Australia
CCPN@latvax8.lat.oz