We've just updated MediaWiki and its underlying software. If anything doesn't look or work quite right, please mention it to us. --RanAS
CMPW (SPC700): Difference between revisions
From SnesLab
m (Jeffythedragonslayer moved page CMPW to CMPW (SPC700): SPC700 in title) |
(made flags affected more prominent) |
||
| (18 intermediate revisions by the same user not shown) | |||
| Line 1: | Line 1: | ||
{| class="wikitable" style="float:right;clear:right;width:40%" | |||
{| class="wikitable" style="float:right;clear:right;width: | |||
!colspan="8"|Basic Info | !colspan="8"|Basic Info | ||
|+ | |+ | ||
| Line 9: | Line 7: | ||
|'''Speed''' | |'''Speed''' | ||
|+ | |+ | ||
| | |[[Direct Page Addressing | Direct Page]] | ||
|5A | |5A | ||
|2 bytes | |2 bytes | ||
| Line 16: | Line 14: | ||
{| class="wikitable" style="float:right;clear:right;width:30%" | {| class="wikitable" style="float:right;clear:right;width:30%" | ||
!colspan="8"|Flags | !colspan="8"|Flags Affected | ||
|+ | |||
|[[Negative Flag|N]] | |||
|[[Overflow Flag|V]] | |||
|[[Direct Page Flag|P]] | |||
|[[Break Flag|B]] | |||
|[[Half-Carry Flag|H]] | |||
|[[Interrupt Enable Flag|I]] | |||
|[[Zero Flag|Z]] | |||
|[[Carry Flag|C]] | |||
|+ | |+ | ||
|N | |N | ||
|. | |. | ||
|. | |. | ||
| Line 33: | Line 31: | ||
|. | |. | ||
|. | |. | ||
| | |Z | ||
| | |C | ||
|} | |} | ||
'''CMPW''' (Compare Word) is an [[SPC700]] command that performs a comparsion between [[YA]] and a 16-bit word in the [[direct page]]. Internally, this is done by the [[ALU]] subtracting the direct page word from YA, but the difference is not stored anywhere - the side effect is the N, Z, and C flags being modified. | |||
==== Syntax ==== | |||
<pre> | |||
CMPW YA, dp | |||
</pre> | |||
=== See Also === | |||
* [[CMP (SPC700)]] | |||
* [[ADDW]] | |||
* [[SUBW]] | |||
* [[MOVW]] | |||
=== External Links === | |||
* Official Nintendo documentation on CMPW: Table C-12 in [https://archive.org/details/SNESDevManual/book1/page/n233 Appendix C-8 of Book I] | |||
* anomie: https://github.com/yupferris/TasmShiz/blob/8fabc9764c33a7ae2520a76d80ed7220bb939f12/spc700.txt#L407 | |||
[[Category:ASM]] | [[Category:ASM]] | ||
[[Category:SPC700]] | [[Category:SPC700]] | ||
[[Category:16-bit Operation Commands]] | [[Category:16-bit Operation Commands]] | ||
[[Category:Two-byte Instructions]] | |||
Latest revision as of 13:55, 30 July 2024
| Basic Info | |||||||
|---|---|---|---|---|---|---|---|
| Addressing Mode | Opcode | Length | Speed | ||||
| Direct Page | 5A | 2 bytes | 4 cycles | ||||
| Flags Affected | |||||||
|---|---|---|---|---|---|---|---|
| N | V | P | B | H | I | Z | C |
| N | . | . | . | . | . | Z | C |
CMPW (Compare Word) is an SPC700 command that performs a comparsion between YA and a 16-bit word in the direct page. Internally, this is done by the ALU subtracting the direct page word from YA, but the difference is not stored anywhere - the side effect is the N, Z, and C flags being modified.
Syntax
CMPW YA, dp
See Also
External Links
- Official Nintendo documentation on CMPW: Table C-12 in Appendix C-8 of Book I
- anomie: https://github.com/yupferris/TasmShiz/blob/8fabc9764c33a7ae2520a76d80ed7220bb939f12/spc700.txt#L407