Difference between revisions of "BC"

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'''BC''' (short for Backwards Compatibility) is a bootloader similar to [[boot1]] that is responsible for verifying and loading [[boot2]]{{check}} in a state that will make it load [[MIOS]]. It is run when a GameCube game is launched from the [[Disc Channel]]. It is unknown why Nintendo did not simply place all of the GameCube compatibility code in MIOS.
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'''BC''' (short for Backwards Compatibility) is a bootloader similar to [[boot1]]. It is responsible for lowering the [[Hardware/Broadway|Broadway]]'s clock speed, then verifying and loading [[boot2]], which will load [[MIOS]] after it detects the lowered clock speed. It is run when a GameCube game is launched from the [[Disc Channel]]. It is unknown why Nintendo did not simply place all of the GameCube compatibility code in MIOS.
  
 
BC can be launched by calling <code>ES_LaunchBC</code> in [[:/dev/es]].
 
BC can be launched by calling <code>ES_LaunchBC</code> in [[:/dev/es]].

Revision as of 23:05, 12 May 2021

BC (short for Backwards Compatibility) is a bootloader similar to boot1. It is responsible for lowering the Broadway's clock speed, then verifying and loading boot2, which will load MIOS after it detects the lowered clock speed. It is run when a GameCube game is launched from the Disc Channel. It is unknown why Nintendo did not simply place all of the GameCube compatibility code in MIOS.

BC can be launched by calling ES_LaunchBC in /dev/es.

Version history

version length build tag / date notes
0 0x41be Aug 11, 2006* corresponds with boot1a?
1 0x412a Sep 2, 2006* corresponds with boot1b?
2 0x414c bc.0611021443
4 0x4d8c bc.0803040819 corresponds with boot1c? Fixes the signing bug.
5 0x4f08 bc.0806101038
6 0x502c bc.0908240243 corresponds with boot1d?

* No build tags are included with early versions of BC, so approximate dates are listed from corresponding MIOS. These dates are likely very close (If not identical) to the actual BC build dates.