NLZ: Difference between revisions

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(New page: {{InstructionBox |Mnemonic=NLZ |Description=Normalize (integer to floating) |Format=NLZ ''<scaling>'' |Code=151 400 |Affected=(T), (A) and (D) }} '''STZ''' is an instruction on the ...)
 
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|Format=NLZ ''<scaling>''
|Format=NLZ ''<scaling>''
|Code=151&nbsp;400
|Code=151&nbsp;400
|Affected=(T), (A) and (D)
|Affected=T, A, D
|Architecture=[[ND-100]], [[ND-110 CPU|ND-110]]
}}
}}


'''STZ''' is an instruction on the ND platform. It converts the number in the [[A register]] to a standard form floating number in [[the floating accumulator]], using the ''scaling'' of the NLZ instruction as a scaling factor.  
'''NLZ''' is an assembly instruction. It converts the number in the [[A register]] to a standard form [[48-bit floating point]] number in the [[floating point accumulator]] (T, A and D registers), using the ''scaling'' of the NLZ instruction as a scaling factor.
 
The ''scaling'' is given to the conversion of -128 to 127 (approximately 10<sup>-39</sup> to 10<sup>39</sup>).


For integers, a scaling factor of +16<sub><small>10</small></sub> will give a floating point number with the same value as the integer. A larger scaling factor will result in a higher floating point number. Because of the single precision fixed point number, the [[D register]] will be cleared.
For integers, a scaling factor of +16<sub><small>10</small></sub> will give a floating point number with the same value as the integer. A larger scaling factor will result in a higher floating point number. Because of the single precision fixed point number, the [[D register]] will be cleared.


== Example ==
== Example ==
*NLZ+20 (code 151420) Convert from integer to floating point.
*NLZ+20 (''code 151420'') Convert from integer to floating point.
 
 
==== NLZ on 32-bit floating point CPUs ====
{{main|32-bit floating point}}
 
The ND-100/110 can have a 48-bit floating point CPU (standard configuration) or a 32-bit floating point CPU (customer option).
For 32-bit floating point operations NLZ works as described above, except that the T register is not affected. This can also be used to test for 48-bit vs. 32-bit CPUs. The method is described in {{ND-doc|06.029.01}}<ref>{{ND-doc|06.029.01}}</ref> p.72:
 
SAT 0    % Set T register to zero (INSTRUCTION-B test program uses 'COPY 0 DT')
SAA 1    % Set A register bit one
NLZ 16  % Normalize with scaling factor 16 decimal
% Test if T is changed (non-zero). If so, the CPU is 48-bit, otherwise it is 32-bit.
 
== References ==
<references/>
*{{ND-doc|06.014.02|pages 120, 144, 146 and 240}}
*{{ND-doc|06.029.01|page 70 and 72}}


== Sources ==
*{{ND-doc|06.014.02|Page 144 and 240}}


[[Category:ND-100 instructions]]
[[Category:ND-100 instructions]]

Latest revision as of 08:48, 21 March 2013

NLZ
Description Normalize (integer to floating)
Format NLZ <scaling>
Code 151 4008
Affected T, A, D
Type User
Architecture ND-100, ND-110

NLZ is an assembly instruction. It converts the number in the A register to a standard form 48-bit floating point number in the floating point accumulator (T, A and D registers), using the scaling of the NLZ instruction as a scaling factor.

The scaling is given to the conversion of -128 to 127 (approximately 10-39 to 1039).

For integers, a scaling factor of +1610 will give a floating point number with the same value as the integer. A larger scaling factor will result in a higher floating point number. Because of the single precision fixed point number, the D register will be cleared.


Example

  • NLZ+20 (code 151420) Convert from integer to floating point.


NLZ on 32-bit floating point CPUs

Main article: 32-bit floating point

The ND-100/110 can have a 48-bit floating point CPU (standard configuration) or a 32-bit floating point CPU (customer option). For 32-bit floating point operations NLZ works as described above, except that the T register is not affected. This can also be used to test for 48-bit vs. 32-bit CPUs. The method is described in Norsk Data Document ND–06.029.01 ND-110 Instruction Set [1] p.72:

SAT 0    % Set T register to zero (INSTRUCTION-B test program uses 'COPY 0 DT')
SAA 1    % Set A register bit one
NLZ 16   % Normalize with scaling factor 16 decimal
% Test if T is changed (non-zero). If so, the CPU is 48-bit, otherwise it is 32-bit.

References

  1. Norsk Data Document ND–06.029.01 ND-110 Instruction Set