Tandy 1000 MS-DOS Reference Manual page 289

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Word Ptr/Byte Ptr
NEG
DEC
Chapter 13 / The DEBUG Utility
BYTE PTR [128]
WO [S 1 ]
DEBUG cannot tell whether some operands refer to a word mem-
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ory location or to a byte memory location. In such a case, the
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WORD PTR
or
BYTE PTR.
These can be abbreviated
wo
and
BY.
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Memory Location/Immediate Operand
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MoV
MoV
AX,21
AX,[21]
;Load AX with 21H
;Load AX wlth the contents of
;memory locatlon 21H
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You use square brackets to tell DEBUG that an operand refers to
a memory location rather than to an immediate operand.
DEBUG uses the convention that operands enclosed in square
brackets refer to memory.
DB/DW Opcodes
Two popular pseudo-instructions are available with the Assemble
command. The DB opcode assembles byte values directly into
memory. The DW opcode assembles word values directly into
memory.
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DB
DB
DB
DW
1 ,2,3,4,"THIS AN EXAMPLE"
'THIS IS A QUOTE:'"
"THIS IS A QUoTE:'"
1fiHl0,2000,3'HHl, "BACH"
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Register Indirect Commands
ADD BX,34[BP+2]. [SI-1]
POP [BP+DI]
PUSH [SI]
All forms of register indirect commands are supported.
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