Betriebssystem/Software für Alphatronic P1

    • Official Post

    Hello jlopez, helwie44 : I have not fully understood the target of your considerations. Is it to read / write 1702 Eproms?


    Here is something that might help

    http://www.tronola.com/html/1702a_prom_programmer.html


    I have updloaded the page here to conserve it.

  • Hello Toshi ,


    My effort is for dumping them only. While having the option to write is a good thing, it's not something I was seeking. My priority is to savage the data contained in the character ROMs, as they aren't accessible to the CPU and couldn't be saved with the RS232 trick.


    Thank you for those schematics. I'm sure they may prove useful.


    Hello helwie44 ,


    For the special voltages, a regulator in case of the -5v (the easy way) and a resistor plus a zener for the -9V should do the trick.

    No, it wouldn't cause any trouble for an unexpanded P2, or an expanded P2 if it does not use the 64K mode.


    A circuit to burn them... that's beyond my skill. I don't see it to be feasible with the voltages supplied by the P2 PSU, especially the 1702A which requires 47V. Toshi 's options seem good to burn the EPROM.


    Regards Toshi  helwie44

    When I tried to list all retro systems I have at home, the "The message is too long, must be under 500 characters" error appears! :lol:

  • Hello jlopez ,

    thanks for the further considerations.


    I did not consider the +47 volt for the 1702 A EPROM program mode.

    I would have looked into a data sheet first.

    Thank you for the helpful links from Toshi.


    So if so then - an external type. Possible via a V24 connection.

    I think something like that later, or to develop the simple variant first.


    EPROM TMS 2716:

    Ok jlopez,

    asimple plug-in card would be possible with the EPROM TMS 2716.