We've just updated MediaWiki and its underlying software. If anything doesn't look or work quite right, please mention it to us. --RanAS
DSP1/Inverse: Difference between revisions
From SnesLab
(created page) |
(general calculation commands) |
||
| (11 intermediate revisions by the same user not shown) | |||
| Line 1: | Line 1: | ||
'''Inverse''' is a DSP1 command. | {| class="wikitable" style="float:right;clear:right;width:15%" | ||
!colspan="8"|Basic Info | |||
|+ | |||
|'''Opcode''' | |||
|10 | |||
|+ | |||
|'''Speed''' | |||
|98 cycles | |||
12.9 μs | |||
|} | |||
'''Inverse''' is a [[DSP1]] command that calculates a floating point multiplicative inverse (reciprocal). | |||
=== Input Parameters === | |||
* a[M] is the coefficient | |||
* b[C] is the exponent (in the range 8002 to 7FFFh) | |||
The total input value is then a*2^b | |||
=== Output Parameters === | |||
* A[M] is the coefficient | |||
* B[C] is the exponent (in the range 8002 to 7FFFh) | |||
=== References === | === References === | ||
* https://archive.org/details/SNESDevManual/book2/page/n292 | * subparagraph 5.1.2 on [https://archive.org/details/SNESDevManual/book2/page/n292 page 3-5-2 of Book II] of the official Super Nintendo development manual | ||
* paragraph 6.2 on [https://archive.org/details/SNESDevManual/book2/page/n324 page 3-6-1 of Book II], lbid. | |||
* https://github.com/bsnes-emu/bsnes/blob/master/bsnes/sfc/coprocessor/dsp1/dsp1emu.cpp#L305 | |||
[[Category:DSP1]] | |||
[[Category:General Calculation Commands]] | |||
Latest revision as of 04:32, 11 January 2024
| Basic Info | |||||||
|---|---|---|---|---|---|---|---|
| Opcode | 10 | ||||||
| Speed | 98 cycles
12.9 μs | ||||||
Inverse is a DSP1 command that calculates a floating point multiplicative inverse (reciprocal).
Input Parameters
- a[M] is the coefficient
- b[C] is the exponent (in the range 8002 to 7FFFh)
The total input value is then a*2^b
Output Parameters
- A[M] is the coefficient
- B[C] is the exponent (in the range 8002 to 7FFFh)
References
- subparagraph 5.1.2 on page 3-5-2 of Book II of the official Super Nintendo development manual
- paragraph 6.2 on page 3-6-1 of Book II, lbid.
- https://github.com/bsnes-emu/bsnes/blob/master/bsnes/sfc/coprocessor/dsp1/dsp1emu.cpp#L305