Commodore 128 Programmer's Reference Manual page 199

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HOW TO ENTER MACHINE LANGUAGE PROGRAMS INTO THE COMMODORE 128 189
COMMAND:
PURPOSE:
SYNTAX:
Compare two areas of memory.
C <address 1> <address 2> <address 3>
<address 1> A number indicating the start address of the area
of memory to compare against.
<address 2> A number indicating the end address of the area
of memory to compare against.
<address 3> A number indicating the start address of the other
area of memory to compare with. Addresses that
do not agree are printed on the screen.
COMMAND: D
PURPOSE: Disassemble machine code into assembly language mnemonics and
operands.
SYNTAX: D [<address>] [<address 2>]
<address> A number setting the address to start the dis
assembly.
<address 2> An optional ending address of code to be dis
assembled.
The format of the disassembly differs slightly from the input format of an assembly. The
difference is that the first character of a disassembly is a period rather than an A (for
readability), and the hexadecimal value of the op-code is listed as well.
A disassembly listing can be modified using the screen editor. Make any changes
to the mnemonic or operand on the screen, then hit the carriage return. This enters the
line and calls the assembler for further modifications.
A disassembly can be paged. Typing aD RETURN causes the next page
of disassembly to be displayed.
EXAMPLE:
D3000 3003
.03000 A9 00
.03002 FF
.03003 DO 2B
LDA #$00
BNE $3030
COMMAND: F
PURPOSE: Fill a range of locations with a specified byte.
SYNTAX: F <address 1> <address 2> <byte>
<address 1> The first location to fill with the <byte>.
<address 2> The last location to fill with the <byte>.
<byte value> A 1- or 2-digit hexadecimal number to be written.
This command is useful for initializing data structures or any other RAM area.