CHAPTER 4 INTERNAL CPU FUNCTION
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User’s Manual U10676EJ3V0UM
Table 4-4. Carry Flag Manipulation Instruction
Instruction (Mnemonic)
Operation and Processing of Carry Flag
Carry flag manipulation
SET1
CY
Sets CY to 1
instruction
CLR1
CY
Clears CY to 0
NOT1
CY
Inverts content of CY
SKT
CY
Skips if content of CY is 1
Bit transfer instruction
MOV1
mem*.bit, CY
Transfers content of CY to specified bit
MOV1
CY, mem*.bit
Transfers content of specified bit to CY
Bit Boolean instruction
AND1
CY, mem*.bit
Takes ANDs, ORs, or XORs content of specified bit
OR1
CY, mem*.bit
with content of CY and sets result to CY
XOR1
CY, mem*.bit
Interrupt service
In interrupt execution
Saved to stack memory in parallel with other PSW
bits in 8-bit units
RETI
Restored from stack memory with other PSW bits
Remark
mem*.bit indicates the following three bit manipulation addressing modes.
•
fmem.bit
•
pmem.@L
•
@H+mem.bit
Example
To AND bit 3 at address 3FH with P33 and output result to P60
MOV
H, #3H
; Sets higher 4 bits of address to H register
MOV1
CY, @H+0FH.3
; CY
←
bit 3 of 3FH
AND1
CY, PORT3.3
; CY
←
CY P33
MOV1
PORT6.0, CY
; P60
←
CY
(2) Skip flags (SK2, SK1, and SK0)
The skip flags record the skip status, and are automatically set or reset when the CPU executes an instruction.
These flags cannot be manipulated directly by the user as operands.
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