BlinkenBone - introduction
Abstract: "BlinkenBone" is a Blinkenlight panel project, first realized first with the Linux single board computer "BeagleBone" . With the BlinkenBone system, you can connect physical or simulated console panels of historical computers to simulations of these computers.
Yet another Blinkenlight project
If you read this, you surely know what a "Blinkenlight panel" is: the front of a historical computer, equipped with lots of lamps and switches. There are still many of them in vintage computer collections, since if an old computer was scrapped, the panel often was preserved.
But the Blinkenlight panel disconnected from its computer is just a nice picture on the wall. You need to add control electronic and machine logic to it, to let it show it's original behaviour .. read: "blinking"!
Clearly every vintage computer nerd is hooked to these console panels. So for years people connected Blinkenlight panels to microcontrollers or PCs and simulated the computers behind. Project BlinkenBone is no exception so far. But of course I think its better than all other projects! And there are reasons:
Proudly presenting the feature list:
- BlinkenBone is able to control the biggest known Blinkenlight console panel on earth. As far as I know, this is the IBM 360/91 console in the Computer History Museum (search for "360/91" on their site).
To drive the 360/91 was one of the #1 development targets, now about 2800 lamps and 1200 switches can be connected to a single BeagleBone!
- to reduce costs and installation overhead, one BeagleBone is able to control several panels. Typically it should drive a whole "Blinkenlight" exhibition room in a computer museum.
- panels are controlled over Ethernet TCP/IP (with WLAN as options). So all kind of remote controlling - including web-interfaces - are business-as-usual ... (just find someone who writes all the software).
- the interface to the Blinkenlight panels is fast enough to show smooth light patterns. This means at least 25 updates per second ... and remember: on a 2300 lamp panel! BeagleBone can transfer 250 kBytes of switch and lamp data per second.
- the interface electronic was designed to sense and drive not just clean 5V TTL signals, but also bare lamps and raw switches. (vintage console panels often were cut off from their computers quite brutally). I/O voltage maybe up to 40V.
- For presentations, the driving electronics including the computer simulation must somehow be integrated into the original console panel. No assumptions about these panels can be made, they come in every shape and sizes. So mechanically the BlinkenBone components are flexible and modular. The simulated computer can run on the BeagleBone itself.
- As controlling software, several options can be run alternatively or in parallel.
- If SimH simulates a machine, it is used.
- For other machines, simple "show programs" could do some blinking and switch reactions.
- Controlling software (= the simulated computer) is intended to run primarily on the BeagleBone.
But for development, it is nice to run this software on a MS-Windows or an dekstop-Linux-PC, and still access the BlinkenBone.
- It is possible to write a software-simulation of a historical console panel and use it instead or parallel to the original one.
Panel simulations also help while developing control programs or working on SimH: You can develop applications for BlinkenBone without carrying the big precious original console panel around with you.
(See here for a real and a simulated PPD-11/70 panel sitting side-by-side).
What made BlinkenBone possible
Some factors supported BlinkenBone on its way:
- It benefits from the appearance of cheap powerful embedded Linux computers in 2011: "Raspberry Pi" even reached mainstream news. Prices are very low for ARM based hardware now, Linux with Ethernet and TCP/IP is for free, and every software which can be compiled with the Gnu Compiler "gcc" can be run.
For a more detailed introduction to the BeagleBone see project "DECbox".
- My computer club CCG has some rare panels in his collection, these always stimulated my phantasy.
- CCG club member Thomas is an electronic engineer and can make every printed circuit board you want.
- And since BlinkenBone is already my 3rd approach on the "blinkenlight" theme, it has a quite mature concept finally.