Operator`s manual

F.ramplea:
I-7000
@
@
Ltut a screen
page
(20
lines of code) starting
at
memory location 7000. Pressing the
@
key
during lisLing halrs rhe lisiing.
This form
ofthe command lists a soeen page start-
ing at
the
instruction
last shown,
plus
1.
L
L7OOO,
O
L7OOO,70OO
L7000,
6000
L345, 567
@
These forms list the instructiom
at address
l@
7000 oriy.
@
@
This form lists addr€ss 345
through 567. Only the
last 20 inshuctions will
actu€lly be visible at the
compleiion ofrhe response
ofthe
system.
The
command Lmmmm differs from Dmmmm
in that Lmmmm disassembles
the contents olmemory.
Example:
EDTT
BUG
E@
r$03
DEBUG
L5000,0
@
5000 A9 03 LDA
DEBUG
t l
Thtu example
Bhows that the Debugger examined
the contents of memory
address 5000
and dfuassembled A9 to LDA. Since A9
must have a one-byte
op€ran4 the Debugger
made the next byte
(the
contents
of address 5001) the
op€rand. Therefore,
although the debugger was only
"asked"
for
the
content
of
location 5000, it showed a certain
amount of int€lig€nce and r€plied by show-
ing the instruction that started
at address 5000.
l
To
illustrate this fuiher, the number 03
corresponds to no inachine code
instruction,
so the Debugg€r wor d interyret
03 as an illegal instructio& and
alert
you
to a
possible
error, as shown
below.
Example!
DEBUG
L5001,0
@
5001,03 ???
DNBUG
How€v€r, ifthe {ir6t instruction you
wrote was LDA
$8A,
then you would
have
obtained the folowing,
apparently inconsistent, results while debuggingl
Example:
DEBUG
L5000,00 A9
8A LDA,fS8A
DEBUG
L5001,0 8A TXA