Re: Changing the screen color/luminance on an OS?

The XL/XE revised edition of "Mapping the Atari" says the following
regarding the checksum on pages 228-229:

65518-65529: Checksum and identification data for the ROM area 57344-65535.
.....
65528-9 Checksum, bytes (LSB/MSB)



"Sc0rpi0" <sc0rpi0@xxxxxxxxxxxxxx> wrote in message
news:dtgkji$7kq$1@xxxxxxxxxxxxxxxxxxxx
Larry:

Yes,
those checksums could be tricky.

If you changing anything in ROM just calculate new chksums
and change it too - cause not only emulators can check it
so more safe is to have them correct. Procedures for checking
ROM does it - vector E4something ;) - I don't remember now,
but it's not necessery to look - its just plain sums of all cells
in particular ROM regions (no CRC or this kind of stuff) :).
One thing to check is what cells are not in sums.
As I can remember it's probably C000-C001 and FFF8-FFF9,
but make sure that's true yourself :).

--
Sc0rpi0
I hated going to weddings.
All the grandmas would poke me saying "You're next".
They stopped that when I started doing it to them at funerals.



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