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LADS.TXT
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#: 13692 S4/Machine Code
13-Feb-88 20:53:08
Sb: #untrapped error
Fm: Rick Joslin 72167,3312
To: Any LADS user
To any of you who use Richard Mansfield's fine assembler, you
probably thought you had made every possible error you could.
I found one while trying to adapt the program to run on the
B-128 that I had never encountered while using the program for
years on my C64. In a nutshell:
lda #bank (you meant to say lda bank, this is the error)
sta somewhere
etc., more code
bank .byte 0
(this is an address label, say $48A9 or something)
Notice that 'bank' is a two byte address, and yet you are
trying to load it into one byte (the accumulator). If lads
stopped and told you this, all would be well, but it won't!
What it does instead is load the low byte of the address into
A, and then somehow gets its address counter off by one byte.
The result is that all the code after lda #bank may look pretty
good on the screen, but will be off by one byte, and your program
will inevitably crash. If you start getting some 'impossible'
crashes after adding some source code, you might look for an
error like this.
Hope this isn't old