The following is a list of mysteries.
General
- What is the CTR abbreviation?
- C may stand for Chiheisen ("horizon" in Japanese, the O3DS's codename being "Project Horizon").
- Not true, Horizon refers to the OS.
Hardware
Why are there two CTRCARD controllers?
Background: Also DSi SoC pinout shows evidence of dual NTRCARD controllers on the final DSi SoC. (This was a planned feature of the DSi before being axed later in development)
Why are there two EMMC controllers?
Theory: At some point during 3DS hardware development there was an idea to split up CTR and TWL nand into two different chips.
Is there a JTAG?
Is there more than one revision of the bootrom?
Background: Bootrom visible portion has been dumped on 3DS, 3DSXL, 2DS, New3DS. All matching exactly.
What is the EMMC controller @ 0x10100000 doing?
Background: There's dead code in NWM referencing it.
Why did they put NTRCARD accessible from ARM11?
Theory: At some point during 3DS hardware development there was a concept where ARM11 ran a menu with DS(i) icons while ARM9 was in TWL mode.
Is there a secret message embedded in the 3DS keyscrambler constant?
Background: TWL keyscrambler constant was Nintendo in Japanese, utf-8 encoded.
What is the PDN abbreviation?
- Power distribution network
Software
What was the problem in "initial program loader" that was mentioned in an FCC filing by Nintendo for 2DS?
Background: http://www.neogaf.com/forum/showthread.php?t=814624&page=1
What did SVC 0x74 in the ARM11 kernel do before it got stubbed?
What is the PTM abbreviation?
Why is the DTCM not used anywhere except bootrom?
Background: Bootrom is known to use part of DTCM as state, memsetting it to 0 when it's done. After that, it is never used again.