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Relative Symbolic Addressing
If the name of a particular location is known, a nearby
location may be specified using the known name and a
numeric offset.
BEG
JMP
JPE
BEG+4
CC
SUB
CALL
$+48
BEG MOV
A,B
HLT
MVI
C, 'B
INR
B
In this example the instruction JMP BEG refers to the MOV
A,B instruction.
B instruction.
I N R
bytes.
This form of addressing can be used to locate
several bytes before or after a named location.
Constants
The Assembler allows the user to write positive or negative
numbers directly in a statement.
decimal constants and their binary equivalents will be used
appropriately.
All unsigned numbers are considered positive.
Decimal constants can be defined using the descriptor "D"
after the numeric value.
default is decimal.)
Hexadecimal constants may be defined using the descriptor
"H" after a numeric value.
Note that a hexadecimal constant cannot start with the
digits A-F.
In this case, a leading 0 must be included.
This enables the assembler to differentiate between a
numeric value and a symbol.
ASCII constants may be defined by enclosing the ASCII
character within single quote marks, i.e., ' C'.
double word constants, two characters may be defined
within one quote string.
Example:
The instruction JPE BEG+4 refers to the
BEG+4 means the address BEG plus four
(This is not required, as the
IE.
+10H, 10H, 3AH, 0F4H.
Self-Contained System
Assembler
Revision 2
They will be regarded as
For
12 - 13
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