Broadway

Broadway is the Wii's main CPU. It is based on the GameCube Gekko CPU design, being almost identical other than an overclock and the addition of a few new features.

A very similar CPU called the "PowerPC 750CL" was released by IBM around the same time as the Broadway and used in a few applications such as printers. It seems to have the same feature set, but is not pin compatible.

New features from Gekko

(following text copied from official document "Summary of changes to Gekko User's Manual to turn it into a Broadway User's Manual")

The major changes from Gekko to Broadway, covered in the UM are:

1) L2 cache configurable for 32-B fetch mode, 64B-fetch mode or 128B-fetch mode
2) Deeper pipelining on the 60x bus, programmable to max depth of 2, 3 or 4
3) Number of BATs is increased from 4 to 8 each for I and D
4) Addition of the HID4 register (SPRN = 1011) to control the new features.
5) TAU functionality is eliminated (but the THRM1-3 regs remain)
6) PLL configuration (processor-to-bus frequency ratio) expanded
7) Several changes to the signal pins - DRTRY, TLBISYNC, PLL_CFG[4]
8) Several Gekko errata are fixed on Broadway.
9) The PVR is initially 0x00087100 on Broadway.

Versions

DD1.0
DD1.01
DD1.2 (final)
DD1.3 (some revision - Broadway A/AA?)
DD2.0 (Broadway-1)

PVR_BROADWAY_BASE 0x00087000

PVR_BROADWAY_DD10 0x00087100

PVR_BROADWAY_DD101 0x00087110

PVR_BROADWAY_DD12 0x00087102

PVR_BROADWAY_DD12i 0x00087112

PVR_BROADWAY_DD13 0x00087103

PVR_BROADWAY_DD13i 0x00087113

PVR_BROADWAY_DD20 0x00087200