Forum Rules and Etiquette

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Arduino PS2 to XT converter

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    Originally posted by bhtooefr View Post
    Early IBM Model Ms actually supported the XT explicitly (and IBM even sold a variant without the LEDs specifically for XTs), and they would (on the latest XT BIOS) switch to XT mode automatically.
    Very interesting, and explains why all of them -- even the clones -- still have vestiges of that in the form of the "mode 1" character set, and the original model M's "Mode 2" which was XT scancodes but with less remap and the extended 101 support.

    Mode 1 did remap and multiple keystrokes to make a 101 act like a 89.

    It would have to mostly be a keyboard side thing -- interesting they had a auto-detect of some sort (and it would require detection given the system side hardware difference) that clone makers didn't copy. On the software side it's not exactly rocket science, and it calls into question why so many clone keyboards had the switch at all.

    Well, except if you didn't have that latest ROM or were on a clone that wouldn't take it... then the mechanical switch makes sense.
    From time to time the accessibility of a website must be refreshed with the blood of owners and designers. It is its natural manure.


      Originally posted by deathshadow View Post
      I have NEVER heard of an AT keyboard working on a PC/XT regardless of BIOS unless it had a switch on it to do so. That's definitely news to me...
      Wellllll...that's what we're all here for - to help and inform each other



        I was quite busy with other projects, but I'm really interested in completing this one. Did anybody get any further on this?


          Originally posted by nc_mike View Post
          Wellllll...that's what we're all here for - to help and inform each other

          Wow what an amazing machine!


            Damn! I built the adapter with a DCCDuino Arduino Nano clone and I get the double keys problem, with every possible combinations of programs listed here...
            Finally, is there something to do with it?
            I'm really hoping to find a PS2 to XT adapter



              I am original author of adapter ..
              I released new version of adapter for Arduino:

              Which fixes many problems.. Hope you will enjoy!

              Report if you have any problems!



                would this new code work on a Teensy 3.2 or will it need converted?


                  I made a test this afternoon (same problem as many : one old XT with monitor, but without keyboard).
                  I'll perhaps look after a real XT keyboard later but for now I've got a good PS/2 keyboard which works on my XT !


                  PS : be aware that the latest code has some changes compared to older version. Il particular, the arduino pins for the XT clock and the PS/2 clock have been inverted.
                  If you just use the schematic of the first post along with the lastest program but without inverting those pins, it won't work.



                    I use a PS/2 keyboard with my XT computer, with an Arduino Micro interface module (fun to use a board as interface which is much faster than the computer itself...).

                    I have suspicions on eventual crashes caused by this layout... I need further testing, but I have quite frequent hangouts of the PC, particularily when I use the french keyboard layout.
                    I'll try to stay in QWERTY and test... anyone has stability issues with this setup ? I also observed that when keypresses are very fast (mostly in games) the arduino system gets completely lost.

                    Otherwise I'll perhaps try this system :

                    It should be much more stable... but there's "logistics" problems for me as I don't own an universal programmer and I don't really want to buy one just for this little project.


                      Originally posted by PePe-fr View Post
                      PS : be aware that the latest code has some changes compared to older version. Il particular, the arduino pins for the XT clock and the PS/2 clock have been inverted.
                      If you just use the schematic of the first post along with the lastest program but without inverting those pins, it won't work.
                      What do you mean with "inverted"? Do I have to place inverter gates like 74LS04 or 74LS14 between the pins of the Arduino and the connectors?
                      With kind regards / met vriendelijke groet, Ruud Baltissen



                        No !

                        I mean that pin 3 & 4 are inverted between the schematic and the latest arduino program.


                          Originally posted by PePe-fr View Post
                          I mean that pin 3 & 4 are inverted between the schematic and the latest arduino program.
                          Ah, je comprend. En Anglais c'est "swapped".
                          I understand. In English it is "swapped" .
                          With kind regards / met vriendelijke groet, Ruud Baltissen