Bank Address Register

Note: this page is likely inaccurate/confusing;

The Bank Address Register (also known as the bank byte) is Nintendo's name for the 8-bit register that fills in the most significant bits of a 24-bit address memory access by the 5A22. It keeps track of what bank the CPU is configured to use. It is cleared to zero on reset.^[2]

WDC calls this register the Data Bank Register (DBR).

PLB, MVN, and MVP modify this register. TSB does not transfer the stack pointer to the DBR despite appearing like a transfer mnemonic.

See Also

• PHB
• Program Bank Register
• Address Bus A

References

1. Figure 2-21-2 on page 2-21-3 of Book I of the official Super Nintendo development manual
2. section 2.5 on page 6 of 65c816 datasheet, https://westerndesigncenter.com/wdc/documentation/w65c816s.pdf