MC68HC705J MOTOROLA [Motorola, Inc], MC68HC705J Datasheet - Page 56

• Manufacturer Part Number: MC68HC705J
• Description: Microcontrollers
• Manufacturer: MOTOROLA [Motorola, Inc]

Central Processor Unit (CPU)
3.6.2.2 Read-Modify-Write Instructions
Technical Data
56
NOTE:
These instructions read a memory location or a register, modify its
contents, and write the modified value back to the memory location or to
the register.
Do not use read-modify-write instructions on registers with write-only
bits.
Central Processor Unit (CPU)
Arithmetic shift left (same as LSL)
Arithmetic shift right
Bit clear
Bit set
Clear register
Complement (one’s complement)
Decrement
Increment
Logical shift left (same as ASL)
Logical shift right
Negate (two’s complement)
Rotate left through carry bit
Rotate right through carry bit
Test for negative or zero
1. Unlike other read-modify-write instructions, BCLR and
2. TST is an exception to the read-modify-write sequence
Table 3-2. Read-Modify-Write Instructions
BSET use only direct addressing.
because it does not write a replacement value.
Instruction
MC68HC705J1A — Rev. 4.0
Mnemonic
BCLR
BSET
TST
COM
ROR
DEC
NEG
ASR
CLR
ROL
ASL
LSR
LSL
INC
(2)
(1)
(1)
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