View Full Version : IBM LPFK - Working!

August 19th, 2008, 03:53 PM
I finally found some docs so that I can make this thing work on a PC. If you don't know what it is, take a look:


Details are here: http://brutman.com/IBM_LPFK/IBM_LPFK.html

August 20th, 2008, 12:29 AM
I'm curious.. couldn't you use USB to power this thing? 500 mA@5V shouldn't be a problem.


August 20th, 2008, 12:45 AM
Is there an overlay for that control pad, or do the tops come off and you inserted descriptions inside? How do you know what the buttons do (they look blank)?

nige the hippy
August 20th, 2008, 02:07 AM
Well I think it's pretty, and at least you know how to drive it. I've got an A5 touch panel I haven't a clue on (although I haven't looked at it for a couple of years now) to be honest if I had a use for it I'd try harder.

August 20th, 2008, 04:57 AM
500ma is a bit more than most serial ports can handle, and I thought that was the limit for a USB device. There is somebody who had the original cord that terminated in an 8 pin DIN who hacked a serial connector onto it and then powered it with a tap from a USB cable:


His version of the LPFK looks exactly like mine, but the protocol is very different. That threw me off the trail for a long time. (I kep thinking that my sample was bad, when in fact I just didn't know how to talk to it.)

The keycaps do not remove - it is designed to be used with templates. I am going to scan one of the templates that I have to make it easier for other people.

And yes, it is a pretty device. :-) What does an A5 look like?

August 20th, 2008, 07:31 AM
I was looking for one of those for my 8085 simulator project, but never could find one. I thought I could use the indicators to represent the data and address bus, as well as the machine status. The buttons could be used to "toggle in" instructions and control the simulator.

Every once in a while I still search ebay for this beast...

August 20th, 2008, 07:49 AM
It does have that 'old school' hex entry keypad flavor to it. But unless you had a serial port on the target machine up and running, it wouldn't be of much use.

There are two on eBay right now.

We've been discussing this on the ClassicCmp mailing list. Somebody mentioned doing a version of 'Life' for it, which I think would be really funny. A scrolling message board is another fun one. (I've lit up a few letters with it already.)

August 20th, 2008, 07:59 AM
Well, the target machine is just a PC running a simulator we wrote. Right now it polls the PC keyboard for keys that perform Halt, Step, Interrupt, etc. I had considered using a specialty keyboard, and I remembered the LPFK from seeing it on another system, a PS/2 that was monitoring and controlling the operation of lanes at a bowling alley. When I went searching (a year or two ago) I couldn't find one. Now, I'm off to check out ebay...

August 20th, 2008, 10:24 PM
Mike, that seems like a nice little gadget. How exactly does it work? The keys are toggle switches or normal buttons?