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Program Counter: Difference between revisions

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* subparagraph 8.1.4 on [https://archive.org/details/SNESDevManual/book1/page/n182 page 3-8-4 of Book I] of the official Super Nintendo development manual
* subparagraph 8.1.4 on [https://archive.org/details/SNESDevManual/book1/page/n182 page 3-8-4 of Book I] of the official Super Nintendo development manual
* Pickens, John. http://www.6502.org/tutorials/6502opcodes.html#PC
* Pickens, John. http://www.6502.org/tutorials/6502opcodes.html#PC
* http://www.6502.org/tutorials/65c816opcodes.html#6.2.1.1
* Clark, Bruce. http://www.6502.org/tutorials/65c816opcodes.html#6.2.1.1


[[Category:ASM]]
[[Category:ASM]]
[[Category:Registers]]
[[Category:Registers]]
[[Category:Inherited from 6502]]
[[Category:Inherited from 6502]]

Revision as of 21:57, 22 July 2024

The Program Counter (PC) keeps track of which instruction is currently executing. If incremented past FFFFh, it wraps around to zero.

The 6502 had 16-bit absolute addressing but only an 8-bit adder, so in emulation mode branches that cross a page boundary incur a one cycle penalty.

On the S-SMP it is 16 bits wide. The low byte is called PCL and the high byte is called PCH.

See Also

References