Computer Hardware User's Guide

RPTS Repeat Single Instruction
13-212
Example RPTS AR5
Before Instruction After Instruction
AR5 00 00FF AR5 00 00FF
PC 0123 PC 0124
RC 0 RC 0FF
RE 0 RE 124
RS 0 RS 124
ST 0 ST 100
LUF 0 LUF 0
LV 0 LV 0
UF 0 UF 0
N 0 N 0
Z 0 Z 0
V 0 V 0
C 0 C 0
Because the block-repeat modes modify the program counter, no
other instruction can modify the program counter at the same time.
Therefore, the repeated instruction cannot be a B
cond , BR,
DB cond , CALL, CALL cond , TRAP cond , RETI cond , RETS cond ,
IDLE, IDLE2, RPTB, or RPTS. If this rule is violated, the PC will be
undefined.
Note:
The RPTS instruction cannot be interrupted because instruction fetches are
halted.