3.5 N64 CPU

N64 CPU is part of the MIPS R4000 family of processors. The N64 CPU consists of the following components:

• an execution unit with a 64-bit register file for integer and floating-point operations
• a 16 KB instruction cache
• an 8 KB writeback data cache
• a 32-entry TLB (Translation Lookaside Buffer) for virtual address to physical address calculation

The Nintendo 64 game runs in kernel mode with 32-bit addressing. 64-bit integer operations are available in this mode. However, the 32-bit C calling convention is used to maximize performance.

For more information on the R4300 and the operating system control of the CPU, see the MIPS Microprocessor R4000 User's Manual, R4300 Specifications, and Chapter 6, "N64 Operating System Overview".