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CBNE (SPC700): Difference between revisions

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'''CBNE''' (Compare Branch Not Equal) is an [[SPC700]] instruction that performs a comparison between the [[accumulator]] and a [[direct page]] value and then branches if they are not equal.  The direct page index is the first operand and also the first byte immediately following the opcode, and the relative branch offset is the second operand, the second byte following the opcode.
'''CBNE''' (Compare Branch Not Equal) is an [[SPC700]] instruction that performs a comparison between the [[accumulator]] and a [[direct page]] value and then branches if they are not equal.  The direct page index is the first operand and also the first byte immediately following the opcode, and the relative branch offset is the second operand, the second byte following the opcode.<sup>[3]</sup>


No flags are affected.
No flags are affected.
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CBNE dp+X, rel
CBNE dp+X, rel
</pre>
</pre>
Where rel is given in two's complement.


=== See Also ===
=== See Also ===
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=== External Links ===
=== External Links ===
* Official Super Nintendo development manual on CBNE: Table C-15, [https://archive.org/details/SNESDevManual/book1/page/n233 Appendix C-8 of book I]
# Official Super Nintendo development manual on CBNE: Table C-15, [https://archive.org/details/SNESDevManual/book1/page/n233 Appendix C-8 of book I]
* anomie: https://github.com/yupferris/TasmShiz/blob/8fabc9764c33a7ae2520a76d80ed7220bb939f12/spc700.txt#L372
# anomie: https://github.com/yupferris/TasmShiz/blob/8fabc9764c33a7ae2520a76d80ed7220bb939f12/spc700.txt#L372
# lbid: https://github.com/yupferris/TasmShiz/blob/8fabc9764c33a7ae2520a76d80ed7220bb939f12/spc700.txt#L270


[[Category:ASM]]
[[Category:ASM]]
[[Category:SPC700]]
[[Category:SPC700]]
[[Category:Branching Commands]]
[[Category:Branching Commands]]

Latest revision as of 19:31, 15 August 2024

Basic Info
Addressing Mode Opcode Length Speed
Direct Page / Program Counter Relative 2E 3 bytes when condition is false: 5 cycles

when condition is true: 7 cycles

Direct Page Indexed by X / Program Counter Relative DE 3 bytes when condition is false: 6 cycles

when condition is true: 8 cycles

Flags Affected
N V P B H I Z C
. . . . . . . .

CBNE (Compare Branch Not Equal) is an SPC700 instruction that performs a comparison between the accumulator and a direct page value and then branches if they are not equal. The direct page index is the first operand and also the first byte immediately following the opcode, and the relative branch offset is the second operand, the second byte following the opcode.[3]

No flags are affected.

Syntax

CBNE dp, rel
CBNE dp+X, rel

Where rel is given in two's complement.

See Also

External Links

  1. Official Super Nintendo development manual on CBNE: Table C-15, Appendix C-8 of book I
  2. anomie: https://github.com/yupferris/TasmShiz/blob/8fabc9764c33a7ae2520a76d80ed7220bb939f12/spc700.txt#L372
  3. lbid: https://github.com/yupferris/TasmShiz/blob/8fabc9764c33a7ae2520a76d80ed7220bb939f12/spc700.txt#L270