XT to PS/2 Converter for Model F

Engicoder

01 Sep 2015, 00:39

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.
xt2ps2-front.jpg
xt2ps2-front.jpg (170.39 KiB) Viewed 3110 times
xt2ps2-rear.jpg
xt2ps2-rear.jpg (182.34 KiB) Viewed 3110 times
XT2PS2-installed.jpg
XT2PS2-installed.jpg (162.94 KiB) Viewed 3110 times
xt2ps2-installed-closeup.jpg
xt2ps2-installed-closeup.jpg (186.52 KiB) Viewed 3108 times
Last edited by Engicoder on 04 Sep 2015, 00:17, edited 1 time in total.

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Muirium
µ

01 Sep 2015, 00:55

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

01 Sep 2015, 01:11

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.

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Muirium
µ

01 Sep 2015, 01:21

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

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Redmaus
Gotta start somewhere

01 Sep 2015, 02:16

Does it say XMIT on the PCB?

Engicoder

01 Sep 2015, 02:17

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

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0100010

01 Sep 2015, 02:33

Image

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Muirium
µ

01 Sep 2015, 02:34

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

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Chyros

01 Sep 2015, 09:52

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

andrewjoy

01 Sep 2015, 10:57

i want one !

Engicoder

01 Sep 2015, 13:51

andrewjoy wrote: 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.

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hypkx
Chasing the Dream

01 Sep 2015, 14:36

I want also one.

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XMIT
[ XMIT ]

01 Sep 2015, 19:47

Engicoder wrote: Yes!! A wee easter egg for a certain someone. :D
Well, then. I guess this means I need one.

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chzel

01 Sep 2015, 20:09

I have an XT that could use one!

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ramnes
ПБТ НАВСЕГДА

04 Sep 2015, 02:28

I am really interested! PMd.

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d33n

04 Sep 2015, 10:18

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

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sz42

06 Sep 2015, 17:27

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...

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macmakkara

07 Sep 2015, 12:26

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

07 Sep 2015, 13:27

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

07 Sep 2015, 14:01

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.

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Muirium
µ

07 Sep 2015, 14:26

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

07 Sep 2015, 14:32

Muirium wrote: 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.

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Muirium
µ

07 Sep 2015, 14:36

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.

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macmakkara

07 Sep 2015, 14:55

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

07 Sep 2015, 15:44

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.

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d33n

08 Sep 2015, 20:02

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$

08 Sep 2015, 23:07

Engicoder wrote:
andrewjoy wrote: 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

08 Sep 2015, 23:17

d33n wrote: 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

11 Sep 2015, 16:05

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.

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Cheesebaron

15 Sep 2015, 19:57

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

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