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Jcc
Restrictions: A Jcc instruction used within a DO loop cannot begin at the address LA
within that DO loop.
A Jcc instruction cannot be repeated using the REP instruction.
Example:
:
JNN – (R4)
:
Explanation of Example: In this example, program execution is transferred to the
address P:(R4)–1 if the result is not normalized. Note that the contents of address regis-
ter R4 are predecremented by 1, and the resulting address is then loaded into the pro-
gram counter (PC) if the specified condition is true. If the specified condition is not true,
no jump is taken, and the program counter is incremented by one.
Condition Codes:
15
14
13
LF
DM
The condition codes are not affected by this instruction.
Instruction Format:
Jcc
xxx
Opcode:
23
0
0
0
0
MOTOROLA
INSTRUCTION DESCRIPTIONS
Jump Conditionally
;jump to P:(R4) –1 if not normalized
12
11
10
9
T
**
S1
S0
I1
MR
16 15
1
1
1
0
C
C
C
INSTRUCTION SET DETAILS
8
7
6
5
4
I0
S
L
E
U
CCR
8
7
C
a
a
a
a
a
Jcc
3
2
1
0
N
Z
V
C
0
a
a
a
a
a
a
a
A - 107
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