We've just updated MediaWiki and its underlying software. If anything doesn't look or work quite right, please mention it to us. --RanAS
GETB (Super FX): Difference between revisions
From SnesLab
(linkify S) |
(added syntax) |
||
| (4 intermediate revisions by the same user not shown) | |||
| Line 2: | Line 2: | ||
!colspan="8"|Basic Info | !colspan="8"|Basic Info | ||
|+ | |+ | ||
|'''Addressing Mode''' | |||
|'''Opcode''' | |'''Opcode''' | ||
|'''Length''' | |'''Length''' | ||
| Line 8: | Line 9: | ||
|'''Cache Speed''' | |'''Cache Speed''' | ||
|+ | |+ | ||
|[[Implied]] (type 1) | |||
|EF | |EF | ||
|1 byte | |1 byte | ||
| Line 37: | Line 39: | ||
'''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. | '''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. | ||
The reason the cycle times can vary is because of the ROM buffer. | R<sub>14</sub> serves as the ROM address pointer. | ||
The reason the cycle times can vary is because of the [[ROM buffer]]. | |||
==== Syntax ==== | |||
<pre> | |||
GETB | |||
</pre> | |||
[[File:gsu_getb.png]] | [[File:gsu_getb.png]] | ||
Latest revision as of 02:27, 6 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.
Syntax
GETB
See Also
External Links
- Official Super Nintendo development manual on GETB: 9.35 on Page 2-9-49 of Book II
- example: page 2-9-50 of Book II, lbid