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Program Bank Register: Difference between revisions

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(instructions that affect it)
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# section 2.9 on page 7 of 65c816 datasheet, https://westerndesigncenter.com/wdc/documentation/w65c816s.pdf
# section 2.9 on page 7 of 65c816 datasheet, https://westerndesigncenter.com/wdc/documentation/w65c816s.pdf
# Figure 2-3-2 Super FX Memory Map on page 2-3-4 of Book II
# Figure 2-3-2 Super FX Memory Map on page 2-3-4 of Book II
# section 3.4 Program Address Space of 65c816 datasheet


[[Category:SNES Hardware]]
[[Category:SNES Hardware]]
[[Category:Registers]]
[[Category:Registers]]

Revision as of 23:45, 31 July 2024

The Program Bank Register (PBR or K) exists on the 65c816. It tells the processor which bank to fetch the next opcode from. It is 8 bits wide. It is cleared to zero on reset.[2] PHK pushes it onto the stack, but there is no PLK to pull it.

PBR is affected only by:

There is also a program bank register on the GSU.[1] It can be used to specify any mapped bank address.[3]

See Also

Reference

  1. paragraph 4.5 on page 2-4-5 of Book II
  2. section 2.9 on page 7 of 65c816 datasheet, https://westerndesigncenter.com/wdc/documentation/w65c816s.pdf
  3. Figure 2-3-2 Super FX Memory Map on page 2-3-4 of Book II
  4. section 3.4 Program Address Space of 65c816 datasheet