About 10 years ago I bought a large lot of HP-41 stuff on Ebay. Included were some unusual ROMs. They've been sitting in a box for years and I am going through all my stuff trying to catalog it.
I have two ROMS that I suspect are HP-41 Diagnostic ROMS. I also have one keyboard overlay that appears to be for a Diagnostic ROM. The two ROMS behave a little differently when inserted in the HP-41.
Both ROMs are blank except for hand written sticky labels. The first one is labeled with a sticker 'P. Diag' on the bottom, and a small round sticker '3/' on the top. When inserted in an HP-41, and the -41 turned on, it immediately beeps 3 quick beeps "Dah-dit dit", and "SELECT TEST" flashes continuously on the display. Most keys don't seem to do anything, but pressing 9 gives "SRV MOD TEST" for a few seconds and then "SM-2B OK". 8 gives "GEN ROM TEST" and then "TM-2C OK" apparently testing the Timer ROM (-41CX). 2 gives "STS REC 0000", USER give "PRESS R/S", and when you do, "Printer TEST", which errors out (no printer connected). 3 gives "EOL TEST" and it too errors out. PRGM and ALPHA give "<AUTO>", but I don't know what it is doing.
The second one is labled "Diag ROM" on a sticker that is where a normal branded label goes, and it has a small red round sticker with a D on it and a small white retangular sticker with "BW" on it, both handwritten. When it is inserted, it beeps the same as the other one, but says "CPU OK" before blinking "SELECT TEST". Many more of the keys do things, and the 9 key gives "SRV MOD TEST" for a few seconds, and then "SM-1:C". There are some others, but these are the ones that have my attention right now.
Did HP release multiple Service ROMS? What are these? Any help graciously accepted.
Dan Grelinger