DEC [R3R2]
Machine code
Description
Operation
DI
Machine code
Description
EI
Machine code
Description
HALT
Machine code
Description
Operation
IN A,Pi
Machine code
Description
Operation
INC A
Machine code
Description
Operation
INC Rn
Machine code
Description
Operation
Preliminary
HTG1390
Decrement data memory
00001111
Data in the data memory specified by the register pair “R3,R2” is decre-
mented by one. Carry flag is not affected.
M(R3,R2) ← M(R3,R2)–1
Disable interrupt
00101101
Internal time-out interrupt and external interrupt are disabled.
Enable interrupt
00101100
Internal time-out interrupt and external interrupt are enabled.
Halt system clock
00110111 00111110
Turn off system clock, and enter power down mode.
PC ← PC+2
Input port to accumulator
PS 0 0 1 1 0 0 1 1
PP 0 0 1 1 0 1 0 0
The data on port “Pi” is transferred to the accumulator.
ACC ← Pi; Pi=PS or PP
Increment accumulator
00110001
Data in the accumulator is incremented by one. Carry flag is not affected.
ACC ← ACC+1
Increment register
0001nnn0
Data in the working register “Rn” is incremented by one. Carry flag is not
affected.
Rn ← Rn+1; Rn=R0~R4 for nnn=0~4
18
17th Nov ’98