We've just updated MediaWiki and its underlying software. If anything doesn't look or work quite right, please mention it to us. --RanAS
MULT (Super FX)
From SnesLab
(Redirected from GSU/MULT)
| Basic Info | |||||||
|---|---|---|---|---|---|---|---|
| Addressing Mode | Opcode | Length | ROM Speed | RAM Speed | Cache Speed | ||
| Implied (type 1) | 8n | 1 byte | 3 or 5 cycles | 3 or 5 cycles | 1 or 2 cycles | ||
| Immediate | 3E8n | 2 bytes | 6 or 8 cycles | 6 or 8 cycles | 2 or 3 cycles | ||
| Flags Affected | ||||||||
|---|---|---|---|---|---|---|---|---|
| B | ALT1 | ALT2 | O/V | S | CY | Z | ||
| 0 | 0 | 0 | . | S | . | Z | ||
MULT is a Super FX instruction that performs a signed multiplication. One of the factors is the low byte of the source register. The other factor may be any register from R0 to R15 or an immediate int from 0 to 15. The product is stored in the destination register.
MULT utilizes the 8-bit multiplier only once, so it is fast.[2]
The exact number of cycles depends on the state of the CFGR register.
The ALT0 state is restored.
The source and destination registers should be specified in advance using WITH, FROM, or TO. Otherwise, R0 serves as the default.
Syntax
MULT Rn MULT #n
Example 1
Let:
Sreg : R5 Dreg : R2 R5 = 52cfh R1 = 63cfh
After executing MULT R1:
R2 = 0961h
Example 2
Let:
Sreg : R3 Dreg : R4 R3 = 95c6h
After executing MULT #9:
R4 = fdf6h
See Also
External Links
- Official Nintendo documentation on MULT: 9.66 on Page 2-9-93 of Book II
- 8.2 "Multiplication Instructions" on page 2-8-16 of Book II, lbid.