SMSC USB464, USB4640i 11Ch-122h:Combo LUN 4 Identifier String, 123h-145h:Not Applicable, 8.4.5.7146h: Dynamic Number of Extended LUNs, 8.4.5.8147h-14Bh:Device to LUN Mapping

High Speed Inter-Chip USB 2.0 Hub and Flash Media Controller

Datasheet
8.4.5.5	11Ch-122h: Combo LUN 4 Identifier String
BYTE	NAME	DESCRIPTION
6:0	CLUN4_ID_STR	If the device to LUN mapping bytes have configured this LUN to be a combo
		LUN, then these strings will be used to identify the LUN rather than the
		device identifier strings.
8.4.5.6	123h-145h: Not Applicable
BYTE	NAME	DESCRIPTION
34:0	Not Applicable	Not applicable.

8.4.5.7146h: Dynamic Number of Extended LUNs

BIT	NAME	DESCRIPTION
7:0	DYN_NUM_	These bytes are used to specify the number of LUNs the device exposes to
	EXT_LUN	the host. These bytes are also used for icon sharing by assigning more than
		one LUN to a single icon. This is used in applications where the device
		utilizes a combo socket and the OEM wishes to have only a single icon
		displayed for one or more interfaces.
		If this field is set to "FF", the program assumes that you are using the default
		value and icons will be configured per the default configuration.

8.4.5.8147h-14Bh: Device to LUN Mapping

BYTE	NAME	DESCRIPTION
4:0	DEV_LUN_MAP	These registers map a device controller (SD/MMC, SM (Note 8.2), and MS)
		to a Logical Unit Number (LUN). The device reports the mapped LUNs to
		the USB host in the USB descriptor during enumeration. The icon installer
		associates custom icons with the LUNs specified in these fields.
		Setting a register to "FF" indicates that the device is not mapped. Setting all
		of the DEV_LUN_MAP registers for all devices to "FF" forces the use of the
		default mapping configuration. Not all configurations are valid. Valid
		configurations depend on the hardware, packaging, and OEM board layout.
		The number of unique LUNs mapped must match the value in the Section
		8.4.3.7, "D3h: Dynamic Number of LUNs," on page 40.

8.4.5.914Ch-17Bh: Not Applicable

BIT	NAME	DESCRIPTION
49:0	Not Applicable	Not applicable.

8.4.5.1017Ch -17Fh: Non-Volatile Storage Signature for Extended Configuration

BYTE	NAME	DESCRIPTION
3:0	NVSTORE_SIG2	This signature is used to verify the validity of the data in the upper 256 bytes
		if a 512 byte (4 kilobytes) EEPROM is used, otherwise this bank is a read-only
		configuration area. The signature must be set to 'ecf1'.
SMSC USB4640/USB4640i		51	Revision 1.0 (06-01-09)

DATASHEET