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The Hollywood includes an ARM9 core to handle I/O and security, nicknamed the Starlet by fail0verflow, but internally known as the IOP, short for Input/Output Processor. This is a very interesting piece of hardware, as it basically does everything that makes a Wii different from a GameCube.

The Starlet contains an internal 96KB SRAM; if IOS needs more memory, it can lock part of MEM2 to prevent Broadway access.

Note: this page is incomplete. Please expand it as you see fit!


  • NEC ARM926EJ-S SoC. See also ChipWorks.
  • Big endian for compatibility with the Broadway
  • ARM and thumb instruction set
  • Clocked at 243MHz (Hollywood clock)


Exception vectors are located at ffff0000. Each exception is given 4 bytes, and usually branches elsewhere.

Index mini name Description
0 v_reset Hardware reset. Typically the entrypoint for official software.
1 v_undf Undefined instruction, used as handler for IOS syscalls
2 v_swi SVC/SWI instruction, used for IOS SWI syscalls
3 v_instr_abrt Instruction abort
4 v_data_abrt Data abort
5 v_reserved Reserved
6 v_irq IRQ
7 v_fiq FIQ


See also: boot process

Starlet is the first processor to run code in the Wii.

  • Starlet boots from an internal Mask ROM, BOOT0 (about 1300 bytes of code out of 4K possible)
  • boot0 decrypts, verifies, and runs the first few blocks of NAND, BOOT1 (up to the first 47 pages of flash)
  • boot1 locates, loads, decrypts, verifies, and runs BOOT2
  • boot2 starts the IOS
  • IOS loads System Menu into memory and bootstraps the Broadway using the EXI boot vector


More information about the Starlet: