Wednesday, November 30, 2011


I thought a bit about the electronics for the console panel. I want to be able to control it remotely from a PC. The PC will need to be able to record input from toggle switches, buttons and rotary controls (potmeters and rotary switches). It will also need to be able to switch the lamps on and off. In total, it will have to provide 183 digital inputs, 237 digital outputs, 5 analog inputs and one analog output (for the voltmeter).
I've opted to use a Velleman K8061 kit. This is a USB interface that provides 8 digital inputs, 8 digital outputs, 8 analog inputs and 8 analog outputs. To control the multitude of switches and lights, I'm going to use shift registers. Lots of them.

The lamps are a bit of a problem. After testing them I found that about half of them are bad and won't light up. They're tiny incandescent bulbs in a plastic casing that plugs into the sockets on the panel. I haven't been able to find replacements for them. Also, the incandescent bulbs would need a buffer stage to connect them to CMOS logic.

Fortunately, the casings are not too hard to open, so I think I'm going to open them up and replace the bulbs with LEDs.

I've just sent off the order for electronics parts to my supplier. I've ordered the Velleman interface kit, a power supply, veroboard, shift registers (74HC595 and 74HC597), orange LEDs, ribbon cable, connectors and a lot of other small items.

First look, planning

The console panel has been identified as belonging to an IBM 360 model 65 mainframe.
The console panel is divided into sections; each section has it's own steel panel (2.5mm or 0.1" thick) with controls mounted on it. The main panel, which has the register lights and address and data toggle switches on it, is wired using yelow-and-orange ribbon cable. The other panels are wired using a wiring harness with a lot of identical (white-orange striped) wires.
Unfortunately, the cables were simply chopped off when the console panel was separated from the cpu. This makes it hard to determine which wire is which. At the console end of the cables, every wire is individually numbered as shown below.
So, the plan is as follows:
- disassemble the panel
- clean up the individual bits and pieces
- rewire the bits that need re-wiring (all the bits that don't use the ribbon cables)
- reassemble the panel
- add some electronics to control the lights and switches from a pc
- create a software interface between the panel and a Hercules emulator running on the pc

Tuesday, November 29, 2011

Console panel arrived

On the morning of the 29th of November, a long awaited pallet arrived at my doorstep. Inside? An IBM 360 mainframe's console panel from the 1960's. This particular one spent part of its life on the desk of a software engineer at Digital Equipment Corporation, IBM's main competitor in that era.
Upon arrival, the contents of the package were seized by our two year old son Ties. I don't believe he left a knob unturned, buttons unpushed or switches untoggled.
As is seen more clearly in the big image below, there is some damage to the panel (note the potentiometer near the upper right corner, it's at an odd angle), and there is some tape residue left behind. On most of the buttons, the text can't be read anymore.