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What does this OI do?


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Sahoo

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PostPosted: Tue Apr 22, 2008 9:29 pm
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What will the following OR Immediate instruction do?
OI WK4BTS+L'WK4BTS-1,X'F0'
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CICS Guy

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PostPosted: Tue Apr 22, 2008 9:36 pm
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It insures that the sign for the ZD field is a 'F' instead of the usual 'C'......
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Sahoo

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PostPosted: Wed Apr 23, 2008 3:44 am
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How is this L'WK4BTS-1 calculated
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CICS Guy

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PostPosted: Wed Apr 23, 2008 3:54 am
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Sahoo wrote:
How is this L'WK4BTS-1 calculated
That should read 'the length of WK4BTS minus one......
If WK4BTS was defined as a length of 9 characters at memory location 100, then
OI WK4BTS+L'WK4BTS-1,X'F0'
would translate as OI 100+9-1,X'F0'
111111111
000000000
012345678
000001234 the hex would be F0F0F0F0F0F0F1F2F3C4
Aand that C4 would be at memory location 100+9-1 or 108......and OI into a F4 so the display would be 000001234 rather than 00000123D....

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manikawnth

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PostPosted: Wed Apr 30, 2008 3:07 am
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I think it is better to say like this:
The usual Zonal decimal format is converted to a character decimal,
as ZD cannot have a signed nibble 'F'
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dick scherrer

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PostPosted: Wed Apr 30, 2008 3:13 am
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Hello,

Quote:
as ZD cannot have a signed nibble 'F'
An "F" sign is treated as positive, just the same as a "C" sign. . .
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CICS Guy

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PostPosted: Wed Apr 30, 2008 3:35 am
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From the PoOps
Chapter 8. Decimal Instructions
Decimal-Number Formats . . . . . . . . . . . 8-1
Zoned Format . . . . . . . . . . . . . . . . 8-1
.
.
.
Zoned Format
In the zoned format, the rightmost four bits of a byte are called the numeric bits (N) and normally consist of a code representing a decimal digit. The leftmost four bits of a byte are called the zone bits (Z), except for the rightmost byte of a decimal operand, where these bits may be treated either as a zone or as a sign (S).

Appendix A. Number Representation and Instruction-Use Examples
Decimal Integers . . . . . . . . . . . . . . . A-4
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.
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The following are some examples of decimal integers shown in hexadecimal notation:
Code:
Decimal Value Packed Format Zoned Format
+123          12 3C         F1 F2 C3
              or            or
              12 3F         F1 F2 F3
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