Control Data 3100 Reference Manual page 90

23 18 1 7 16 1 5 14
00
02 10
I
b
(Approximate execution time: 2.6 fJ,sec.)
m
b
=
index register designator
m
=
jump address
Instruction Description: If b = 1, 2, or 3, the respective index register is examined:
1.
If
(B~
= 00000, the jump test condition is not satisfied; RNI from address P
+
1.
2.
If (B
b
)
=F
00000, the jump test condition is satisfied. One is added to (B
b
);
jump to address
m and RNI.
Comments: If
b=
0,
this is a no-operation instruction; RNI from address
P
+
1. Indirect
addressing and jump address modification may not be used. The counting operation is done
in a one's complement additive accumulator. Negative zero (77777) is not generated because
the count progresses from: 77775, 77776, to 00000 (positive zero) and stops. If negative zero
is initially loaded into B
b
,
the count progresses: 77777, 00001, 00002, etc. In this case, the
counter must increment through the entire range of numbers to reach positive zero.
RNI from
address
P
+
1
7-33
Instruction in F
Jump to address
'm'; RNI
Rev. B