reverse order. Now we can scroll to the two zeros at $0801 and
type over them 12 08 and hit RETURN. The first four bytes
starting at $0801 should now be 12 08 01 00 (the 01 00 bytes
represent the current line number in reverse 01 00=00 01). Our
Basic program is now repaired and all that's left is to locate
the end of the program and save it to your backup disk. To find
the program end, use the HUNT command in your monitor. We'll
hunt for the three zero bytes that signal the end of Basic.
<>H 0801 8000 00 00 00 <>. As the first bytes begin to be
reported, hit the number 1 key to stop the hunt. We are only
interested in the first address reported. In this case, it
should be $1C15. Using the MEMORY command, inspect memory around
the address $1C15. You will notice that the third zero is at the
location $1C15. We now have all the information needed to save
the new boot to your backup. The start address is $0801
(beginning of Basic) and the end address is $1C16 (all monitors
require us to save the actual address plus one: $1C15+1=$1C16).
Make sure your backup is in the drive and save the memory from
$0801-$1C15 <> S "AH",08,0801,1C16 <>.
When the save is complete, you will have a broken copy that will
no longer do a protection check. We have essentially replaced
the auto boot and the protection check with the result, a Basic
boot.
SUPERBOWL SUNDAY : AVALON HILL
Procedure:
Loading the original produces a rattle free load, and an error
scan shows no standard errors. A backup made with the C-64 Fast
Copier produces a non-working copy. A backup made with a nybbler
produces the same non-working copy. Before starting to work on this
program, please make a non-working backup of the original.
Working with your backup:
1) Start by validating the BAM <> OPEN15,8,15,"V":CLOSE15 <> to
make room for a new file we will be adding later. Scratch the
first file from the backup <> OPEN15,8,15,"S0:START":CLOSE15 <>.
Working with your original:
2) Place a write protect tab on the original to ensure its safety
during the breaking process.
3) Turn your computer off and insert the reset assembly into the
cartridge port. Turn the computer on again and load the boot
file and start the load process <> LOAD"START",8,1 <>. Allow the
K.J. REVEALED TRILOGY PAGE [16] (C)1990 K.J.P.B.
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