Commodore PC Ms-Dos 3.2 User's Manual page 285

Debug 213
n ___^^
Assemble (A)ssemble
<^ Purpose:
Assembles 8086/8087/8088 mnemonics directly into memory.
(^ Syntax:
A[address]
!^ Comments:
If a syntax error is found, debug responds with the following
•—v message, then redisplays the current assembly address:
AError
f) All numeric values are hexadecimal and you must type them as
1—4 characters. Also, you must specify prefix mnemonics in front
of the opcode to which they refer. You may type them on a
r**} separate line, however.
The segment override mnemonics are CS:, DS:, ES:, and SS:.
The mnemonic for the far return is RETF. String manipulation
f00^ mnemonics must explicitly state the string size. For example, use
MOVSW to move word strings, and use MOVSB to move byte
strings.
{***} The assembler will automatically assemble short, near, or far
jumps and calls, depending on byte displacement, to the destina
tion address. You may override these jumps and calls by using a
f0*^ NEAR or FAR prefix, as in the following example:
01
01
01
00:0500
00:0502
00:505
JMP
JMP
JMP
502
NEAR
FAR
505
50A
; a 2-byte
; a 3-byte
; a 5-byte
short
near
far j
j ump
j ump
ump
rv
You may abbreviate the NEAR prefix to NE, but the FAR prefix
f0**) cannot be abbreviated.
Debug cannot tell whether some operands refer to a word
memory location or to a byte memory location. In this case, the
{***) data type must be explicitly stated with the prefix, WORD PTR
or BYTE PTR Acceptable abbreviations are WO and BY. For
example:
^* NEG BYTE PTR [128]
DEC WO CSI]