This page documents the format of NCSD.

Overview

There are two known specialisations of the NCSD container format. The CTR Cart Image (CCI) format and the CTR System Update (CSU). CCI is the format of retail game ROM dumps. CSU is used with developer system updates and tools

NCSD images start with a NCSD header, followed by up to a maximum of 8 NCCH partitions. The first partition(NCCH 0) usually starts at 0x4000, this is generally the main NCCH (Executable). The following info on partitions 1, 2, and 7 are only valid for .CCI. The second partition(NCCH 1) contains the game "Manual"(title ID for the .CFA containing the Manual always starts with '0005'). The third partition(NCCH 2) contains the download play "Child"(The title ID for the .CFA containing the DLP Child always starts with '0006'). The eighth block(NCCH 7) contains "Update Data"(The title ID for the .CFA containing the Update Data always starts with '8000') The format of partitions can be determined from the partition FS flags, while the contents can be determined from the partitions flags.

NCSD header

Offset Size Description
0x000 0x100 RSA-2048 SHA-256 signature of the NCSD header
0x100 4 Magic Number 'NCSD'
0x104 4 Size of the NCSD image, in media units (1 media unit = 0x200 bytes)
0x108 8 Media ID
0x110 8 Partitions FS type
0x118 8 Partitions crypt type
0x120 0x40=(4+4)*8 Offset & Length partition table
0x160 0x20 Exheader SHA-256 hash
0x180 0x4 Additional header size
0x184 0x4 Sector zero offset
0x188 8 Partition Flags: byte[5]-byte[7] indicate content type ( system update, application, manual, ... ) size of media units ( 512*2^byte[6] ) and encryption.
0x190 0x40=8*8 Partition ID table
0x1D0 0x30 Reserved


Card Info Header

OFFSET SIZE DESCRIPTION
0x200 8 Card Info
0x208 0xDF8 Reserved1
0x1000 8 Media ID (same as first NCCH partitionId)
0x1008 8 Reserved2
0x1010 0x30 Initial Data
0x1040 0xC0 Reserved
0x1100 0x100 Copy of first NCCH header (excluding RSA signature)

Development Card Info Header Extension

OFFSET SIZE DESCRIPTION
0x1200 0x200 CardDeviceReserved1
0x1400 0x10 TitleKey
0x1410 0xF0 CardDeviceReserved2