Immediate Addressing: Difference between revisions

Revision as of 13:43, 8 August 2024

Immediate Addressing is when the data to be operated on directly follows the opcode in the instruction steam. The immediate data is generally preceded by a # in the assembler source.

Supported by the following 65c816 instructions:

ADC (opcode 69)
SBC (opcode E9)
EOR (opcode 49)
AND (opcode 29)
ORA (opcode 09)
LDA (opcode A9)
LDX (opcode A2)
LDY (opcode A0)
CMP (opcode C9)
CPX (opcode E0)
CPY (opcode C0)
BIT (opcode 89)
SEP (opcode E2)
REP (opcode C2)

They are all either 2 or 3 bytes long.

The Super FX supports immediate addressing too:

ADC
ADD
AND
BIC
SUB
OR
MULT
IWT
IBT
LINK
and presumably UMULT too

On the SPC700, "imm" means "8-bit immediate data."^[4] These commands support immediate data:

MOV (Group 1)
ADC
SBC
CMP
AND
OR
EOR

Syntax

LDA #const

References

Eyes & Lichty, page 397
lbid, page 108
Labiak, page 209
Appendix C-1 of Book I of the official Super Nintendo development manual
section 3.5.18 of 65c816 datasheet, https://westerndesigncenter.com/wdc/documentation/w65c816s.pdf
Clark, Bruce. http://www.6502.org/tutorials/65c816opcodes.html#5.14

@@ Line 54: / Line 54: @@
 === References ===
 # [[Eyes & Lichty]], [https://archive.org/details/0893037893ProgrammingThe65816/page/397 page 397]
-# lbid, page 108: https://archive.org/details/0893037893ProgrammingThe65816/page/108
+# lbid, [https://archive.org/details/0893037893ProgrammingThe65816/page/108 page 108]
 # [[Labiak]], [https://archive.org/details/Programming_the_65816/page/n219 page 209]
 # [https://archive.org/details/SNESDevManual/book1/page/n226 Appendix C-1 of Book I] of the official Super Nintendo development manual

Revision as of 13:43, 8 August 2024

Syntax

See Also

References