Screen flip for SNK Athena


At the request of a friend I was asked to fix the inverted screen issue with Athena.

An hour or so at the hands of the MAME debugger and a couple of false attempts the resulting patch is a simple two byte change to the rom.

In rom up02_p4.rom change these bytes. (actually, the patch swaps them around)

$029e to $48
$02a4 to $3e

Burn a new 27c128 rom and its done. Since we are swapping two bytes, the checksum doesn’t change.

Edit: Tested on a real pcb. Works perfectly as expected 🙂

8 thoughts on “Screen flip for SNK Athena”

    1. You should be able to contact me through here. Sorry I’ve taken so long to reply. Did you want something specific?

  1. Hello

    Yes, i want to know if if your “high score save” eproms program who saves over 10 millions points for Juno First is still available ?
    I am interested.
    If you want, you can contact me by mail.


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