gc80c510 CORERIVER Semiconductor, gc80c510 Datasheet - Page 46

• Manufacturer Part Number: gc80c510
• Description: Eprom/rom 8-bit Turbo Microcontrollers
• Manufacturer: CORERIVER Semiconductor

6.2.1.4 Read-Modify-Write Instructions
exception is the read-modify-write category of instructions. They are listed as follows:
Table 6-4 Read-Modify-Write Instructions
latch. Thus the operation takes place using the value that was originally written to the SFR, without
regard to the pin state. The last three instructions listed above are read-modify-write because they read
the entire port latch, then write back the changed value. In this case, only one bit will be changed as
specified by the instruction.
The normal read instructions will read the pin state without regard to the output data latch. The only
The read-modify-write instructions read the state of the latch, and then write back the result to the
MOV PX.Y, C
Instruction
SETB PX.Y
CLR PX.Y
DJNZ
ANL
ORL
XRL
JBC
CPL
INC
DEC
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Logical AND
Logical OR
Logical Exclusive OR (XOR)
Branch if bit is set then clear bit
Complement bit
Increment
Decrement
Decrement and branch if not zero
Move the carry bit to bit Y of Port X
Clear bit Y of Port X
Set bit Y of Port X
Description
Functional Description