Testing the prototype of the console hw - part 1

In order to validate the design of the physical console that will provide the lights, buttons, switches, keyboard and printer of the IBM 1130, I put together prototypes and wired up a test to prove it out before finalizing construction plans.

The display light panels were formed using LEDs in the final pattern that will be illuminated behind a plexiglas panel in the pedestal unit that sits above the console printer on the IBM 1130. These were cabled to the display drivers, fanout logic, concentrators, switch debouncers and data links, which were attached to the FPGA 1130 and tested. Switches from scrap panels of IBM 3420 are used, along with toggle switches for the Console Entry Switch group temporarily mounted on a cardboard rectangle, and a rotary switch to be used for the Mode switch on the pedestal were wired in to test actual hardware components intended for the replica 1130.

The keyboard and console printer elements are not yet ready for testing, although temporary logic is provided to allow a PS/2 keyboard to be used for entry. The key layout is matched, but the keycap markings, shapes and colors are not the same as the 1130 and the feel is completely different. It will allow debugging and use of the system until the final keyboard mechanism is constructed. Similarly, emulation is provided for the IBM 1053 device used as the console printer, emitting ascii over the fpgalink to a PC which will display what is being 'typed' by the console device. These two emulated portions will be tested a bit later, followed by prototype testing of the final designs once my keyboard and printer hardware is ready.

Prototype of light panel being constructed

1130 Pedestal Light Panel

The buttons and lights near the keyboard will be similar to these, although mined from scrap 3420 tape drive and scrap buttons found on ebay. These are wired through the debouncer to the concentrator. 
1130 Buttons and Lamps near the keyboard
Scrap 3420 panel to provide buttons and lamps
The keyboard itself is repurposed from the 029 Keypunch, and that would be the first choice if I can get my hands on a keypunch or the parts, otherwise I will need to come as close as possible.
Keyboard of the 1130 (or 029)

The Console Entry Switches go through their own concentrator board, one I received from Richard Stofer, wired to some toggle switches bought on ebay. These are not an exact substitute for the 1130 switches but are very long toggle handles to permit mounting in a realistic setting in front of the console printer.
1130 Console Entry Switches

My CES prototype with R. Stofer's board
The Console Entry Switches work well, tested and used with the load and display modes of the machine.
Once the switches are mounted in their more permanent location on the console printer faceplate, this will be fully usable.

The test setup with the console display lights hooked into the 1130 - not working properly initially, recoding along with testing to fine tune. Didn't put enough capacitors protecting the + power to the board, to avoid the impacts of all the current switching into and out of the LED array. This removed glitches to yield a much more reliable transfer to the MAX7219 chips. Found a few bad LEDs, some broken wires in the harness and a few unsoldered leads on my prototype board. Cleaned up and moved on to debugging the displayed state of the lights. There are still glitches occuring, thus more work needed on the prototype board, as well as some wiring issues remaining in the right hand board. Progress is steady, however, and it is only a matter of time before this is solid enough to consider the design final. At that point I will design a production printed circuit board and build it.

Testing the light display panel hardware

The button and switch entry unit were debugged, then tested with the 3420 tape unit buttons hooked through the debouncer board to the multiplexor board, whose link worked well with the console link function inside the fpga. Work is now underway to design a final printed circuit board for the button/switch entry logic, merging the debouncer and multiplexor boards into one. This will be fabbed by an outside service and then components soldered on after I receive the board.

When the production version circuit boards are built, I will conduct a second round of testing/debugging of the completed system. 

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