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AT2XT keyboard converter

tonata said:
I found this keyboard: key tronics E03602 EL FR (french one).

It seems XT compatible, but these are not switches on the second photo. Instead there are 3 holes. Do I need to solder switches myself? For XT compatibility I have to connect the 3 of them? It is not clear to me how to configure it.
Click to expand...
I also have an AT-class Key Tronic keyboard (a different model to yours) that is similar; no switch soldered on. When I added a suitable switch, it made no difference. It appears that at some point, Key Tronic decided to drop support for the XT protocol, by removing the XT related code in the keyboard's ROM, and removing the XT-AT switch (but kept using the same case).

Your Key Tronic keyboard may be the same (i.e. adding a switch does nothing).

If you want to try adding a switch, you would need to pull the keyboard apart to investigate further (e.g. determine size restrictions for switch, holes for switch pins, ...)

The white outline on the PCB suggests a slide type of switch. An example (repeat: example) is shown at [here].


( BTW. The 'PCs and clones' forum would have been a better place for your post. )
 
gekaufman said:
I've had a few emails lately asking about PC boards and assembled units. I got a bit carried away and ordered/built up a batch of these with 3D printed cases etc. I still have some spares if anyone is looking for one.

- Gary
Click to expand...

How much for a complete unit (if you have more left)?

-Sterling
 
gekaufman said:
I've had a few emails lately asking about PC boards and assembled units. I got a bit carried away and ordered/built up a batch of these with 3D printed cases etc. I still have some spares if anyone is looking for one.

- Gary
Click to expand...

How much for a complete unit (if you have any left)?
-Sterling
 
Hey, everyone -

I have an amazingly good build of this from a gentleman in Bulgaria - and it appears to be pretty awesome. I'm using it on my Tandy 1000 SL/E (which uses the XT protocol), and am having issues with missing keypresses, and some keypresses not showing the correct character. I'm using a Mitsumi PS/2 keyboard (with an AT adapter) - beige. I've also tried a five pin DIN AT keyboard (which was confirmed working on another system). Both keyboards exhibit the same results. Note, that this is a Tandy which accepts a Tandy 1000 101 Key enhanced keyboard, so it's not the original Tandy keyboard.

Any suggestions to where I can start figuring out what's going on?

Edit: Here's the unit https://www.ebay.com/itm/283738884563?ul_noapp=true - The seller sent me directly to this thread saying he used the design from here.

Thanks!
 
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acadiel said:
Any suggestions to where I can start figuring out what's going on?
Click to expand...
Member schnurzel came up with some alternative firmware for the converter's PIC chip. It maybe the answer. Available at [here].

You will need a device that can program the firmware into the 12F629 PIC chip. Alternatively, some of the people/companies at [here] could supply a programmed 12F629 for you.
 
modem7 said:
Member schnurzel came up with some alternative firmware for the converter's PIC chip. It maybe the answer. Available at [here].

You will need a device that can program the firmware into the 12F629 PIC chip. Alternatively, some of the people/companies at [here] could supply a programmed 12F629 for you.
Click to expand...

Thanks!

My 844USB can program those - I'll give it a try.
 
modem7 said:
Member schnurzel came up with some alternative firmware for the converter's PIC chip. It maybe the answer. Available at [here].

You will need a device that can program the firmware into the 12F629 PIC chip. Alternatively, some of the people/companies at [here] could supply a programmed 12F629 for you.
Click to expand...

I've got the chips and programmer, but I'm a bit stuck at what I need to care about at this screen... have any guidance? Thanks!

options_pic.png
 
acadiel said:
I've got the chips and programmer, but I'm a bit stuck at what I need to care about at this screen... have any guidance? Thanks!
Click to expand...
I am unfamiliar with that programmer, but the operation should be as simple as read in the HEX file, then program the chip.
 
I am having an odd bug/issue with my AT2XT.
I am using Sergey's Micro8088 and the AT2XT that is part of the design.
Most everything seems to be working correctly except...

Shift + arrow keys.
If I use the numpad, shift+arrow keys work as expected in edit.com and other text editors to highlight text.
If I use the inverted T arrow keys, shift+arrow key acts as if shift is not being held and the cursor moves with no highlighting.

I am setup to convert my CF card to a virtual disk image and back, all of that works reliably. So using the exact same drive image & utilities, shift + inverted T arrows works as expected in VirtualBox, so I'm left pointing fingers at the AT2XT.

Is this a known issue, is this something I missed in configuration?

Thank you.
 
I found references to this problem online. The only suggestion was to upgrade from 0.94 to 0.1d. I've tried that with no change to the shift + inverted T arrow keys behavior.

I may be expecting behavior that can't happen or otherwise misunderstand AT2XT, as I have a key scanning program which shows some odd behaviour of the shift key pressing itself when using the inverted T arrow keys, so I'm guessing the AT2XT is translating the arrow keys into num pad arrow presses depending if Numlock is on or not.
 
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modem7 said:
Member schnurzel came up with some alternative firmware for the converter's PIC chip. It maybe the answer. Available at [here].

You will need a device that can program the firmware into the 12F629 PIC chip. Alternatively, some of the people/companies at [here] could supply a programmed 12F629 for you.
Click to expand...

The alternate firmware above worked great with my Tandy 1000 SL/E.

Just wanted to let everyone to know - try that firmware if you have a Tandy 1000 SL/TL/RL/RLX system.
 
deathshadow said:
This guy:
http://www.kbdbabel.org/

Has done several strange keyboards to AT converters, including PC/XT. I agree with @Stone it's not the most useful of directions to my mind, but it has been done. If anything the simpler protocols are easier to read than AT, making such conversion actually simpler to implement than the other direction.

It's one of the sources I've been using for information -- and what led me to question the PC/XT timing info I was seeing as the math on his charts:

http://www.kbdbabel.org/signaling/index.html

... don't seem to add up right, and are inconsistent with how most clocked protocols have a delay to compensate for rise/fall time.
Click to expand...
Wow this is nice. I have seen some old keyboards at my friend's home and they were really amazing. If you want I can share some of the images of it with you.
 
does anybody has a working HEX for "Zenith Z-150 XT(black label)" keyboard

it has different signals
I found info about it

This is a "normal" XT keystroke with the DATA line held normally low, and CLK normally high. When ready to send a code, 10 CLK falling edges are sent: 2 start bits, 8 data bits, for a total of 10 bits:

Image

This is a keystroke from the Z-150. The DATA line is held normally high (opposite). When ready to send a code, only 9 CLK falling edges are sent for a total of 9 bits. I'm guessing there is only 1 start bit.
Click to expand...

the text is taken from here , also there a pictures from logic analyzer

https://deskthority.net/viewtopic.php?f=2&t=12972&start=30#p354189
 
What happen if I permanently solder the R3 resistor for the E0 pass-through, will it still work for US keyboards?
 
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