TRS-80 / System 80

From: Tony Duell <ard_at_p850ug1.demon.co.uk>
Date: Tue May 6 17:33:09 2003

> Interestingly enough, it mentions checking the temperatures of the RAM (ICs
> Z27 through Z34) as part of the official RAM troubleshooting procedure - hot
> RAM -> "REPLACE RAM", apparently. Replacements are to be "4116 type Dynamic

The Radio Shack technical manual warns you that a RAM with supply line
shorts can get up to soldering-type temperatures, and that you should be
careful touching the RAMs to detect a bad one...

> To reset the machine, apparently it's necessary to hold down 'Break' and
> 'Reset' at the same time.

On a TRS-80 with a disk controller, this will cause it to ignore the disk
system and run the ROM BASIC. It's the way to start up a disk-based
machine (or any M1 with an expansion interface, which contains the disk
controller) without a system disk.

-tony
Received on Tue May 06 2003 - 17:33:09 BST