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and given the sign of the packed-decimal number
ending at location 5603. Also assume:
Register 12 contains 00 00 56 00.
Register 15 contains 00 00 45 00.
Storage locations 5600-5603 contain 77 88 99 OC.
Storage locations 4500-4502 contain 12 34 56.
After the instruction:
Machine Format
Op Code
B 1
°
1
F1
3
2
C
I
0001
F
I
000\
Assembler Format
Op Code
D1(Ll,Bl),02(L2,B2)
MVO
0(4,12),0(3,1S)
is executed, the storage locations 5600-5603
contain 01 23 45 6C. Note that the second
operand is extended on the left with one zero to fill
out the first-operand field.
MOVE ZONES (MVZ)
The MOVE ZONES instruction can, similarly to
MOVE (MVC) and MOVE NUMERICS, operate
on overlapping or nonoverlapping fields. When
operating on nonoverlapping fields, MOVE ZONES
works like the MOVE NUMERICS instruction (see
the example for MOVE NUMERICS), except that
MOVE ZONES moves only the zone bits of each
byte. To illustrate the use of MOVE ZONES with
overlapping fields, assume that the following data
field is in storage:
800
80S
Also assume that register 15 contains 00 00 08
00. The instruction:
Machine Format
Op Code
L
B 1
D 1
03
04
F
I
0001
Assembler Format
Op Code
01(L,B1),D2(B2)
MVZ
l(S,lS),O(lS)
propagates the zone bits from the byte at address
800 through the entire field, so that the field
becomes:
800
80S
IF1IF2IF3IF4\FS\F61
MULTIPLY (M, MR)
Assume that a number in register 5 is to be
multiplied by the contents of a word at address
3750. Initially:
The contents of register 4 are not significant.
Register 5 contains 00 00 00 9A
=
15410
=
the
multiplicand.
Register 11 contains 00 00 06 00.
Register 12 contains 00 00 30 00.
Storage locations 3750-3753 contain 00 00 0083
=
13110
=
the multiplier.·
The instruction required for performing the
multiplication is:
Machine Format
Op Code
SC
4
B
Assembler Format
Op Code
R1,02(X2,B2)
M
4,X ' 1S0 ' (11,12)
After the instruction is executed, the product is
in the register pair 4 and 5:
Register 4 contains 00 00 00 00.
Register 5 contains 00 00 4E CE
=
20,17410'
Storage locations 3750-3753 are unchanged.
The RR format of the instruction can be used to
square the number in a register. Assume that
register 7 contains 00 01 00 05. The instruction:
Machine Format
Op Code
1C
6
7
Assembler Format
Op Code
R1,R2
MR
6,7
Appendix A. Number Representation and Instruction-Use Examples
A-19
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