[vcf-midatlantic] Workshop HP recap

[Mike Loewen]

    I worked on the museum's HP 2117F system all weekend, with mixed results. 
My objectives were to install missing boards in the CPU, evaluate the 7912 
hard disc (65MB), and install the RTE-6/VM OS, if possible.

    Summary:

1. Populated the 2117F with additional RAM and the HP-IB controller

2. The 2621P terminal works

3. The 7912 appears to work

4. RTE-6/VM wouldn't completely load

5. We need a cable for the terminal, and a 13181A board set for the 7970B

    The warehouse has two HP 2113E units, which I used for spare parts. I 
pulled the 12821A (HP-IB) controller board and a 12749H (256K Word) memory 
board from one, and a memory connector cable and 7970 tape boot ROM from the 
other. The museum system now has 1M Word of ECC RAM installed. I removed a 
duplicate 264X CTU (Cartridge Tape Unit) boot ROM and replaced it with the 
7970 (9-track tape) ROM. The old ROM is taped to the inside of the front 
panel. We're still missing the 13181A two-board set for the 7970B tape drive 
in the system rack (it wasn't in the system when we got it). I will continue 
to look for a board set that doesn't cost an arm and a leg.

    The I/O cage has a F.E.M. (Firmware Expansion Module) with the RTE6 
OS/VMA/EMA and SIS (Scientific Instruction Set) ROMS installed. Also installed 
are the TBG (Time Base Generator), the 12821A (HP-IB) controller, and three 
BACI (Basic Asynchronous Communication Interface) boards to connect to 
terminals.

    The HP 2621P terminal in the museum also works, although the battery which 
maintains the settings is either dead or missing (I didn't look). It needs a 
cable to connect to the 2117F, which I may be able to make. I brought a cable 
from my terminal for testing.

    The 7912 hard disc appears to work. It spun up the first time, and passed 
its self-test. I was able to image the drive with a PC running the HPDir 
program, so I can inspect the data later on. I copied a RTE-6/VM image to the 
7912, which I had prepared with the SimH hp2100 emulator for the specific 
configuration of the museum system.

    The bad news is that the 2117F would not successfully boot from the 
emulated drive (HPDrive) on the PC, or the 7912 drive. It would load from the 
drive, then go into what I was told is an "idle loop". Nothing was ever 
displayed on the terminal. I was able to load diagnostics from my HPDrive 
system, and output from the Diagnostic Configurator displayed on the terminal. 
I started running diagnostics, but ran out of time on Sunday and had to stop.

    My HP guru thinks that there may be a problem with the Time Base Generator, 
or the interrupt chain starting with the FEM. The next chance I get, I will 
run further diagnostics on the memory and suspect boards.

    The CPU is still available to run the "Cylon" demo program, keyed in from 
the front panel. Power for the system will be a concern when the hard drive is 
up and running. At one point, it tripped the breaker for the row of micros it 
was powered from. The HP cabinet has a power controller with a (I believe) 
220V plug, which we may want to eventually use. It would eliminate the need to 
power on/off each unit individually.


Mike Loewen				mloewen at cpumagic.scol.pa.us
Old Technology				http://q7.neurotica.com/Oldtech/