Functional Description
www.ti.com
Table 26-20. Configuration Header TOC Item
Offset Field Size (Bytes) Value Description
Offset from the start address of
0x0000 Start 4 0x000000a0 TOC to the actual address of a
section.
0x0004 Size 4 0x00000050 Size of a section
0x0008 Reserved 4 Unused
0x000C Reserved 4 0x00000000 Unused
0x0010 Reserved 4 Unused
0x45534843 12-character name of a
section, including the zero (\0)
0x4e495454
0x0014 Filename 12 terminator (these are the
ASCII characters for
0x00005347
'CHSETTINGS').
0x0020 Closing item 4
0x0024 Closing item 4
0x0028 Closing item 4
0x002C Closing item 4
32 bytes of 0xFF to signify the
0xFFFFFFFF
end of the TOC item.
0x0030 Closing item 4
0x0034 Closing item 4
0x0038 Closing item 4
0x003C Closing item 4
Table 26-21. Configuration Header Settings
Offset Field Value Description
0000h Section key 0xC0C0C0C1 Key used for section verification
Enables or disables the section.
0004h Valid 0x00
00h: Disable.
Other: Enable.
Configuration header version.
0005h Version 0x001
Others: For future use
0006h
Set the reset of the header (offset
... Reserved 0x00
0x6 to 0xe0) to 0x00.
0xe0
26.1.7.5.6 MMC/SD Read Sector Procedure in FAT Mode
MMC/SD Cards may hold a FAT file system which ROM Code is able to read and process. The image
used by the booting procedure is taken from a specific booting file named “MLO”. This file has to be
located in the root directory on an active primary partition of type FAT12/16 or FAT32.
An MMC/SD card can be configured either as floppy-like or hard-drive-like.
• When acting as floppy-like, the content of the card is a single file system without any Master Boot
Record (MBR) holding a partition table
• When acting as hard-drive-like, an MBR is present in the first sector of the card. This MBR holds a
table of partitions, one of which must be FAT12/16/32, primary and active.
The card should always hold an MBR except for MMC cards using floppy-like file system (please refer to
the CSD internal Register fields FILE_FORMAT_GRP and FILE_FORMAT in the MultiMedia Card System
Specification). However, depending on the used operating system the MMC/SD card will be formatted
either with partition(s) (using an MBR) or without. The ROM Code supports both types; this is described in
the following section.
4132
Initialization SPRUH73H–October 2011–Revised April 2013
Submit Documentation Feedback
Copyright © 2011–2013, Texas Instruments Incorporated
To Next Page
Loading...
Need help?
General
