4501_M Datasheet, PDF (82/212 Pages) Renesas Technology Corp – 4-BIT CISC SINGLE-CHIP MICROCOMPUTER 4500 SERIES

4501 Group
HARDWARE
INSTRUCTIONS
MACHINE INSTRUCTIONS (INDEX BY ALPHABET) (continued)
OP2A (Output port P2 from Accumulator)
Instruction
code
D9
D0
Number of Number of Flag CY
words
cycles
1 0 0 0 1 0 0 0 1 0 ₂ 2 2 2 ₁₆
1
1
–
Skip condition
–
Operation: (P21, P20) ← (A1, A0)
Grouping: Input/Output operation
Description: Outputs the contents of the low-order 2 bits
(A1, A0) of register A to port P2.
OR (logical OR between accumulator and memory)
Instruction
code
D9
D0
Number of Number of Flag CY
words
cycles
0 0 0 0 0 1 1 0 0 1 ₂ 0 1 9 ₁₆
1
1
–
Skip condition
–
Operation: (A) ← (A) OR (M(DP))
Grouping:
Description:
Arithmetic operation
Takes the OR operation between the con-
tents of register A and the contents of
M(DP), and stores the result in register A.
POF (Power OFf1)
Instruction
code
D9
D0
Number of Number of Flag CY
0000000010
002
words
cycles
2
16
1
1
–
Skip condition
–
Operation:
RAM back-up
However, voltage drop detection circuit valid
Grouping: Other operation
Description: Puts the system in RAM back-up state by
executing the POF instruction after execut-
ing the EPOF instruction.
However, the voltage drop detection circuit
is valid.
Note:
If the EPOF instruction is not executed before
executing this instruction, this instruction is
equivalent to the NOP instruction.
POF2 (Power OFf2)
Instruction
code
D9
D0
Number of Number of Flag CY
0000001000
008
words
cycles
2
16
1
1
–
Skip condition
–
Operation: RAM back-up
Grouping: Other operation
Description: Puts the system in RAM back-up state by
executing the POF2 instruction after ex-
ecuting the EPOF instruction. Operations of
all functions are stopped.
Note:
If the EPOF instruction is not executed be-
fore executing this instruction, this
instruction is equivalent to the NOP instruc-
tion.
Rev.2.01 Feb 07, 2005
REJ09B0192-0201
1-70