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GETB (Super FX): Difference between revisions

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(The ALT0 state is restored.)
(→‎External Links: added ref)
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* Official Super Nintendo development manual on GETB: 9.35 on [https://archive.org/details/SNESDevManual/book2/page/n205 Page 2-9-49 of Book II]
* Official Super Nintendo development manual on GETB: 9.35 on [https://archive.org/details/SNESDevManual/book2/page/n205 Page 2-9-49 of Book II]
* example: [https://archive.org/details/SNESDevManual/book2/page/n206 page 2-9-50 of Book II], lbid
* example: [https://archive.org/details/SNESDevManual/book2/page/n206 page 2-9-50 of Book II], lbid
* page 2-7-1 of Book II, lbid.


[[Category:ASM]]
[[Category:ASM]]

Revision as of 01:46, 16 July 2024

Basic Info
Addressing Mode Opcode Length ROM Speed RAM Speed Cache Speed
Implied (type 1) EF 1 byte 3 to 8 cycles 3 to 9 cycles 1 to 6 cycles
Flags Affected
B ALT1 ALT2 O/V S CY Z
0 0 0 . . . .

GETB (Get Byte) is a Super FX instruction that loads one byte from the ROM buffer into the low byte of the destination register. The high byte of the destination register is zeroed.

R14 serves as the ROM address pointer.

The reason the cycle times can vary is because of the ROM buffer. The ALT0 state is restored.

The destination register should be specified in advance using WITH or TO. Otherwise, R0 serves as the default.

Syntax

GETB

Example

Let:

ROM buffer = 0075h
Dreg : R0

After executing GETB:

R0 = 0075h

gsu getb.png

See Also

External Links