• Update for mk2 v1.1 boards

    fjkraan • 01/08/2022 at 13:38 • 0 comments

    The MicroKit09 mk2 v1.1 CPU board has a serious shortage with address lines, so isn't really production ready. It is fixable however, with some wires
    - All repairs can be done on the solder side
    - Cut both traces to U2-2
    - Add wire between U4-1 and U7-19 (this fixes A10)
    - Add wire between J3-1 and U2-2 (this fixes A12)
    - Add wire between J4-3 and J3-3 (this fixes A11)
    This solution has the disadvantage that the jumper J3 cannot be used anymore to select a 2k byte RAM.

    The MicroKit09 mk2 v1.1 I/O board is ok and is tested with the low profile switches and keys. An image is added to the project gallery.

    The monitor (1.8 and 1.9) has the annoying habit of not showing locations which have no memory. This can be fixed by nopping out two instructions in the EXMEMO call, just past the PREXIN label:

        CMPA ,S+     ; MEMOIRE ABSENTE OU MEMOIRE MORTE?
    LBNE RPOINT     ; OUI, ALLUMER PROMPT ET SCRUTER

    Needs more testing however.

    It it not sure I will create, test and publish newer versions of the boards.