Kapffer@DMZRZU71.BITNET (Matthias Kapffer) (02/07/90)
Recently I no longer wanted to accept the battery RAM trashing of Photonix
(its always writes the absolute number of copies made and -on demand only- the
current configuration to the battery RAM). I found it calling the documented
low level routine at $E10080 in one place for both informations; therefore,
the following patch will keep it from doing so - i.e. NO count AND NO
configuration will clutter your battery RAM (valid for version 1.4 as
distributed via APPLE2-L, all values in sedecimal):
- With a sector editor, search for the four bytes 22 80 00 E1 (a JML E10080);
I found them in block 177 at the relative address 92.
- Change 22 to AF (turns JML into a appropriate (dummy) LDA) and
00 to 8D (to keep Photonix' self-checksum feature happy).
Finally, you have to reset the already changed values in the battery RAM to
their default values. The quickest and dirtiest method is to
option-control-reset the control panel to 50 or 60 Hz defaults - of course
this will kill all your personal preferences. Several of the battery RAM
savers in the public domain enable you (together with BASIC.SYSTEM to patch
the bytes) to correct the flawed values only, but I don't remember exactly
which they were - could be at relative addresses $C0 and $C1.
I hope the above information to be valueable for somebody else.
Matthias Kapffer
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