CBNE (SPC700): Difference between revisions

Revision as of 17:14, 24 July 2023


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 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.

External Links

Official Super Nintendo development manual on CBNE: Appendix C-8 of book I

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-'''CBNE''' is an [[SPC700]] instruction that performs a comparison between the [[accumulator]] and a [[direct page]] value and then branches if they are not equal.
+'''CBNE''' 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.
 === See Also ===