* Selecting CTRCARD2 will activate the register space at [[CTRCARD|0x10005000]].
* Selecting CTRCARD2 will activate the register space at [[CTRCARD|0x10005000]].
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== 0x10000000, Hidden bootrom off-switch ==
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== REG_SYSPROT9 ==
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The ARM9 and ARM11 [[Memory_layout|bootroms]](+0x8000) are disabled by writing 1 to (u8*)0x10000000 and 1 to (u8*)0x10000001?(These two registers are written by the ARM9)
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Writing values to SYSPROT sets the specified bitmask. The ARM9 [[Memory_layout|bootrom]](+0x8000) is disabled by writing bit0. bit1 is used by NATIVE_FIRM to make sure console-unique TWL AES-keys are only set at hard-boot. It is not possible to set any other bits.
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Writing values here(u8 0x10000000+0) sets the specified bitmask. Thus, writing value 0x2 when the register(u8 0x10000000+0) was previously set to value 0x1 changes the value to 0x3. During the NATIVE_FIRM ARM9 kernel startup, it will check if bitmask 0x2 in this register is set. If that bitmask is not set, the console-unique portions of the two console-unique TWL [[AES|keyslots]] are then initialized. The kernel then writes value 0x2 to this register, regardless of the previous bitmask value(due to this, the console-unique TWL key-data init is only done at hard-boot).
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== REG_SYSPROT11 ==
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ARM11 bootrom (+0x8000) is disabled by writing bit0. It is not possible to set any other bits.