LAN9730 Datasheet, PDF (36/222 Pages) SMSC Corporation – High-Speed Inter-Chip (HSIC) USB 2.0

LAN9730/LAN9730i
Note 4-2
Note 4-3
Value is loaded from EEPROM, but must be equal to the default value in order to comply with the USB
2.0 Specification and provide for normal device operation. Specification of any other value will result
in unwanted behavior and untoward operation.
Default value is dependent on device release. The MSB matches the device release and the LSB is
hardcoded to 00h. The initial release value is 01h.
4.3.1.6.2 Configuration Descriptor
The Configuration Descriptor is initialized based on values stored in EEPROM. Table 4-5 shows the default Configura-
tion Descriptor values.
TABLE 4-5: CONFIGURATION DESCRIPTOR
Offset
Field
Size
(Bytes)
Default Value
Loaded from
EEPROM
Description
00h bLength
1
01h bDescriptorType
1
02h wTotalLength
2
04h bNumInterfaces
1
05h bConfigurationValue
1
06h iConfiguration
1
07h bmAttributes
1
08h bMaxPower
1
09h
02h
0027h
01h
01h
00h
A0h
Note 4-6
Note 4-4
Note 4-5
Note 4-4
Note 4-4
Note 4-4
Yes
Yes
Yes
Size of the Configuration Descriptor in
bytes (9 bytes)
Configuration Descriptor (0x02)
Total length in bytes of data returned
(39 bytes)
Number of interfaces
Value to use as an argument to select
this configuration
Index of String Descriptor describing
this configuration
Bus powered and remote wakeup
enabled.
Maximum power consumption is
500 mA.
Note 4-4
Value is loaded from EEPROM, but must be equal to the default value in order to comply with the USB
2.0 Specification and provide for normal device operation. Specification of any other value will result
in unwanted behavior and untoward operation.
Note 4-5
The descriptor type for Configuration Descriptors specified in EEPROM is a “don’t care” and is always
overwritten by hardware as 0x02.
Note 4-6 Default value is 01h in Self-Powered mode and FAh in Bus Powered mode.
Note: The RMT_WKP strap affects the default value of bmAttributes.
DS00001946A-page 36
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