Broadway/Clock Speed Control

Prerequisites

In order to change the clock speed from 729 MHz (stock) to 486 MHz (GameCube mode), or back, you will need code execution on Starlet. Attempting these steps on Broadway results in catastrophic failure, and will not successfully change the clock speed.

Notes

• This appears to potentially have some unknown effect on the coherency of memory, sometimes causing what would appear to be memory corruption. This should probably be investigated further. In the mean time, you may want to ensure that you don't have anything important in MEM1 (and possibly MEM2?) before you do the switch.

Switching modes

In order to from 729 MHz to 486 MHz, the steps are as follows:

• Turn off Broadway
• Set the FX bit in HW_CLOCKS
• Clear the RSTB_DSKPLL bit in HW_RESETS
• Set the SPEED bit in HW_CLOCKS
• Set the RSTB_DSKPLL bit in HW_RESETS
• Clear the FX bit in HW_CLOCKS
• Hollywood is now at 162 MHz, and Broadway is now at 486 MHz

In order to switch back to 729 MHz, you can follow these steps but clear the SPEED bit rather than setting it^[check].