NLZ: Difference between revisions
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The ND-100/110 can have a 48-bit floating point CPU (standard configuration) or a 32-bit floating point CPU (customer option). | 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. | 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 == | ||
Revision as of 09:47, 25 May 2011
| 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
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
- Norsk Data Document ND–06.014.02 ND-100 REFERENCE MANUAL pages 120, 144, 146 and 240
- Norsk Data Document ND–06.029.01 ND-110 Instruction Set page 70 and 72
- ↑ Norsk Data Document ND–06.029.01 ND-110 Instruction Set