CBM Game Cartridge Configuration

ncoplin_at_orbeng.com
Date: 2001-07-25 10:47:02

Hi All,

I have noticed something I cannot understand when I tried to reverse
engineer the schematic for a couple of CBM cartridges. The cartridges have
jumpers which are either soldered or not depending which memory config is
needed.

When configured for games running in Ultimax mode, the /IO2 line is often
found to be connected to the EXROM line. I can only decipher this to mean
that access to $DF00 will map in the ROM to $8000. But what holds it there??
Would it not disappear without a capacitor or something to hold the EXROM
line low?

- Nick


PLEASE TAKE NOTE:

The contents of this email (including any attachments) may be
privileged and confidential. Any unauthorised use of the contents
is expressly prohibited. If you have received this email in error,
please advise us immediately (you can contact us by telephone
on +61 8 9441 2311 by reverse charge) and then permanently
delete this email together with any attachments. We appreciate
your co-operation.

Whilst Orbital endeavours to take reasonable care to ensure
that this email and any attachments are free from viruses or other
defects, Orbital does not represent or warrant that such is explicitly
the case

(C) 2000: Orbital Engine Company (Australia) PTY LTD and its
affiliates


       Message was sent through the cbm-hackers mailing list

Archive generated by hypermail 2.1.1.