The values of these shift bit operators are all constant values. The expression is shifted right
SHR or left SHL by the number of bits specified by count. If bits are shifted out of position, the
corresponding bits that are shifted in are zero-filled. The following are such examples:
mov A, 01110111b SHR 3 ; result ACC=00001110b
mov A, 01110111b SHL 4 ; result ACC=01110000b
·
Bitwise operators NOT, AND, OR, XOR
-
Syntax
NOT expression
expression1 AND expression2
expression1 OR expression2
expression1 XOR expression2
NOT is a bitwise complement.
AND is a bitwise AND.
OR is a bitwise inclusive OR.
XOR is a bitwise exclusive OR.
·
OFFSET operator
-
Syntax
OFFSET expression
The OFFSET operator returns the offset address of an expression. The expression can be
a label, a variable, or other direct memory operand. The value returned by the OFFSET operator
is an immediate operand.
·
LOW, MID and HIGH operator
-
Syntax
LOW expression
MID expression
HIGH expression
The LOW/MID/HIGH operator returns the value of an expression if the result of the expres-
sion is an immediate value. The LOW/MID/HIGH operators will then take the low/middle/high
byte of this value. But if the expression is a label, the LOW/MID/HIGH operator will take the
values of the low/middle/high byte of the program count of this label.
· BANK operator
- Syntax
BANK name
The BANK operator returns the bank number allocated to the section of the name declared. If the
name is a label then it returns the rom bank number. If the name is a data variable then it returns
the ram bank number. The format of the bank number is the same as the BP defined. For more
information of the format please refer to the data sheets of the corresponding MCUs. (Note: The
format of the BP might be different between MCUs.)
Example 1:
mov A, BANK start
mov BP,A
jmp start
Chapter 4 Assembly Language and Cross Assembler
123
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