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SX48BD/SX52BD/SX52BD75/SX52BD100
16.1
Equivalent Assembler Mnemonics
Some assemblers support additional instruction mne-
monics that are special cases of existing instructions or
alternative mnemonics for standard ones. For example,
an assembler might support the mnemonic CLC (clear
carry), which is interpreted the same as the instruction
clrb $03.0 (clear bit 0 in the STATUS register). Some of
the commonly supported equivalent assembler mnemon-
ics are described in Table 16-2.
Table 16-2. Equivalent Assembler Mnemonics
Syntax
Description
Equivalent
Cycles
CLC
Clear Carry Flag
CLRB $03.0
1
CLZ
Clear Zero Flag
CLRB $03.2
1
JMP W
Jump Indirect W
MOV $02,W
3
JMP PC+W
Jump Indirect W Relative
ADD $02,W
3
MODE imm4
Move Immediate to MODE
Register
MOV M,#lit
1
NOT W
Complement W
XOR W,#$FF
1
SC
Skip if Carry Flag Set
SB $03.0
1 or 2 (note 1)
SKIP
Skip Next Instruction
SNB $02.0 or SB $02.0
2 (note 2)
Note1: The SC instruction takes 1 cycle if the tested condition is false or 2 cycles if the tested condition is true.
Note2: The assembler converts the SKIP instruction into a SNB or SB instruction that tests the least significant bit
of the program counter, choosing SNB or SB so that the tested condition is always true.