XT to PS/2 Converter for Model F

[Engicoder]

Why? Why not? Anyway, here it is, a converter that allows you to use the original cable for the Model F XT and use it with a PS/2 computer or adapter. It uses an ATTiny85, so its pretty cheap and simple.

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[Muirium]

Smart. How are you going to mount it in place? Or are you just relying on the tension of those internal cables? I suspect it would flap about a bit, but I could be wrong.

The only DIN 5 (AT / XT) port I have in the house is on my Soarer's Converter box anyway, as I'm a Mac guy. But I appreciate the elegance you've come up with here. Nice one.

[Engicoder]

The wire is 24 gauge so there isn't much movement. A piece of double sided tape could remove all doubt. It could also be done a connector soldered directly to the board so that it would be held rigidly in place by the locking connector.

[Muirium]

Good point about that locking socket. If we ever put Bluetooth in these boards, it ought to clip straight in there!

[Redmaus]

Does it say XMIT on the PCB?

[Engicoder]

Yes!! A wee easter egg for a certain someone. Also happens to identify the purpose of the associated LED.

[0100010]

[Muirium]

Now all we need is a posse of preferably horse mounted DT users called Power, Caps, Scroll and Num.

[Chyros]

Whoa, that's actually really elegant =o . Nice work!

[andrewjoy]

i want one !

[Engicoder]

i want one !

I had to order 10 pcbs, so if anyone wants one, just let me know. The parts I used total about $8-9. I'd be glad to put one together for anyone that is interested.

[hypkx]

I want also one.

[XMIT]

Yes!! A wee easter egg for a certain someone.

Well, then. I guess this means I need one.

[chzel]

I have an XT that could use one!

[ramnes]

I am really interested! PMd.

[d33n]

Very nice and elegant solution, I would love one for my recently bought XT!

[sz42]

Very nice piece of kit that!

I just rescued a near mint Model F XT from going to the scrap heap and was considering what I should do with it. Hmm... interesting...

[macmakkara]

I also have XT that would need on of these... but i believe that you can't mod layout with this? this is just converter?

[andrewjoy]

I don't know , but you could use software for that , the advantage of this is you can go grab your XT and plug it into an PS/2 or AT port and you are good to go.

[Engicoder]

Yes, it can do layout modification (i.e. keymap), but it requires rebuilding the source code at this point. I am working on a PS/2 to USB converter that could be used to update the keymap of this device while in-place.

[Muirium]

Oooh! I wonder what you've got in mind for the USB cable.

XT, AT and USB all use 4 internal wires, so it's possible to pass USB signals over that big original cable, and then either cut off the bulky original 5 pin DIN plug from the end to replace with a USB head, or build a little DIN to USB dongle. Neither thing is as elegant as simply plugging it into an AT port, but not many of us have those these days!

[Engicoder]

Oooh! I wonder what you've got in mind for the USB cable.

XT, AT and USB all use 4 internal wires, so it's possible to pass USB signals over that big original cable, and then either cut off the bulky original 5 pin DIN plug from the end to replace with a USB head, or build a little DIN to USB dongle. Neither thing is as elegant as simply plugging it into an AT port, but not many of us have those these days!

Actually, that's not possible. USB uses differential signaling (like Ethernet, CAN, RS-485, etc) which requires twisted pair wiring. PS/2 cables do not have the data lines as a twisted pair.

[Muirium]

It's not possible in theory, but I do stuff like that in practice! Not through such a long wire as an XT's, though.

[macmakkara]

Hmmm.. Engi is it possible to but one of these from you?

Or are you going to releace PCB file and list of component needed?
Also what would i need to reprogram that attiny85 chip?

[Engicoder]

I will release the source code, hardware files and BOM on GitHub shortly, but I have a few more of the prototype boards for people who want one of the early ones. I will be sending them out this week.

[d33n]

I can't wait for the source code! I have a trinket around here somewhere that might work with that. https://www.adafruit.com/products/1501

[idollar]

i want one !

I had to order 10 pcbs, so if anyone wants one, just let me know. The parts I used total about $8-9. I'd be glad to put one together for anyone that is interested.

If possible, I also would like to have one.

[Engicoder]

I can't wait for the source code! I have a trinket around here somewhere that might work with that. https://www.adafruit.com/products/1501

If you have the 5V version, that should work.

[Engicoder]

I assembled and programmed the boards and am ready to send them out. I sent out invoices as well.

The converter contains a basic keymapping cabability that supports 2 layers. Switching layers is controlled by any single key and can be programmed to be toggle or momentary. With toggle, pressing and releasing the designated switch key will toggle the current layer. With momentary, pressing the designated switch key will switch from layer 0 to layer 1 and releasing will switch back from layer 1 to layer 0. The keymap also supports mod+key combinations that map to a single keystroke. These are used to support the default PC/XT combinations, like Ctrl+NumLock => Pause and Ctrl+ScrollLock => Break.

If anyone who is receiving one would like to have a keymap programmed, I will send you a text file that you can fill out with your map preference and I program it before I send it to you.

[Cheesebaron]

Do you have any more of these? I just received a XT board that I could use this for.