Is the CPU 32 bit or 64 bit?
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Recursive Acronym
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Is the CPU 32 bit or 64 bit?
Wikipedia says that the PSP has a "32-bit MIPS32 R4k-based CPU", although it is elsewhere documented that the R4k (R4000) is a 64-bit CPU. Which is it?
Re: Is the CPU 32 bit or 64 bit?
It's not a R4000 (they probably meant MIPS32-4k and everyone misunderstood). It implements a slightly modified MIPS32R2 ISA.Recursive Acronym wrote:Wikipedia says that the PSP has a "32-bit MIPS32 R4k-based CPU", although it is elsewhere documented that the R4k (R4000) is a 64-bit CPU. Which is it?
it is mostly a modified version named Allegrex based on R4100 with no 64-bit support at all. if i'm not wrong, all MIPS32R2 SPECIAL2 instructions are mapped to the SPECIAL instructions space instead of the usual SPECIAL2 instructions space for instance, which is why using a vanilla MIPS gcc generating those SPECIAL2 instructions might be incompatible with Allegrex (not something i checked).