4552 Datasheet, PDF (88/145 Pages) Renesas Technology Corp – SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER

4552 Group
MACHINE INSTRUCTIONS (INDEX BY ALPHABET) (continued)
RD (Reset port D specified by register Y)
Instruction
code
D9
D0
Number of Number of Flag CY
0000010100
014
words
cycles
2
16
1
1
–
Skip condition
–
Operation:
(D(Y)) ← 0
However,
(Y) = 0 to 7
Grouping: Input/Output operation
Description: Clears (0) to a bit of port D specified by reg-
ister Y.
RT (ReTurn from subroutine)
Instruction
code
D9
D0
Number of Number of Flag CY
0001000100
044
words
cycles
2
16
1
2
–
Skip condition
–
Operation:
(PC) ← (SK(SP))
(SP) ← (SP) – 1
Grouping: Return operation
Description: Returns from subroutine to the routine
called the subroutine.
RTI (ReTurn from Interrupt)
Instruction
code
D9
D0
Number of Number of Flag CY
0001000110
046
words
cycles
2
16
1
1
–
Skip condition
–
Operation:
(PC) ← (SK(SP))
(SP) ← (SP) – 1
Grouping: Return operation
Description: Returns from interrupt service routine to
main routine.
Returns each value of data pointer (X, Y, Z),
carry flag, skip status, NOP mode status by
the continuous description of the LA/LXY in-
struction, register A and register B to the
states just before interrupt.
RTS (ReTurn from subroutine and Skip)
Instruction
code
D9
D0
Number of Number of Flag CY Skip condition
0001000101
045
2
16
words
1
cycles
2
–
Skip at uncondition
Operation:
(PC) ← (SK(SP))
(SP) ← (SP) – 1
Grouping: Return operation
Description: Returns from subroutine to the routine
called the subroutine, and skips the next in-
struction at uncondition.
Rev.3.02 Dec 22, 2006 page 88 of 142
REJ03B0023-0302