Cart hacking

Galpus · Post by **Galpus** » Sun Apr 17, 2005 12:07 pm

Been trying to adapt a 16K cart to take a 27128 EPROM, have it wired in with the 7400 to control the 2 x 8K banks, but it is not working for some reason

I'm not really familar with the VIC20 at all, and only have the cart port pinout to go on.

Anyone have more information on this ?

Thanks...

Leeeeee · Post by **Leeeeee** » Sun Apr 17, 2005 5:43 pm

Do you have a circuit, or a detailed description, of what you're trying to do?

Lee.

Galpus · Post by **Galpus** » Tue Apr 19, 2005 5:35 am

Hi, I just removed the 16K ROM from a Pirate's Cove cartridge which has the
74LS00 (wired to the BLK's and A13 on ROM) and has bank selects 1,2,3,5 for
each bank (Pirate Cove was set at 2,3).

I checked how the ROM was wired with the cart slot pinout, and it was the
same as a 27128, so I soldered in a socket. I then opened up the soldered
banks selects and just set it to bank 5, and then placed an 8K image on the
EPROM as a test, but it just booted-up without running the code.

This should work yes ?

Leeeeee · Post by **Leeeeee** » Tue Apr 19, 2005 7:25 pm

It's possible that ..

.. you got the image in the wrong half of the EPROM.

.. the ROM has active high chip selects.

.. the ROM is two 8KB roms in one package.

.. any, or none, of the above.

Lee.