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=== Other ranges 0x0500'0000 - 0x7FFF'FFFF (External bus via PI) ===
=== Other ranges 0x0500'0000 - 0x7FFF'FFFF (External bus via PI) ===
All accesses made by the VR4300 in these ranges are forward externally by RCP on the external bus via PI. This allows the CPU to access external devices like the cartridge ROM and SRAM.
All accesses made by the VR4300 in these ranges are forward externally by RCP on the external PI bus. This allows the CPU to access external devices connected to the parallel bus like the cartridge ROM and SRAM.


Accesses in this area are affected by the same simplified SysAD implementation described above, so '''access size is ignored.''' The effect is the same described before.
Accesses in this area are affected by the same simplified SysAD implementation described above, so '''access size is ignored.''' The effect is the same described before.
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=== Range 0x8000'0000 - 0xFFFF'FFFF (Unmapped) ===
=== Range 0x8000'0000 - 0xFFFF'FFFF (Unmapped) ===
This range is not handled by RCP. All writes are ignored, and reads lock up the VR4300 because the RCP does not return any data on the bus.
This range is not handled by RCP. All writes are ignored, and reads lock up the VR4300 because the RCP is stalled and does not return any data on the bus.