TallyGenicom 2440, User Manual

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Interfaces USB interface
B-7
Configuration Descriptor
Interface Descriptor Alternate Setting
Offset Field Size Value Description
0 bLength Byte 0x09 Size of this descriptor in bytes.
1 bDescriptorType Byte 0x02 Configuration descriptor type.
2 wTotalLength Word 0x0019 No. of bytes in this configura-
tion. This includes the configu-
ration descriptor plus all of
interface and endpoint descrip-
tors.
4 bNumInterfaces Byte 0x01 Project SDM500 has 1 inter-
face.
5 bConfigurationValue Byte 0x01 Value to use as an argument to
SetConfiguration() request to
select this configuration.
6 iConfiguration Byte 0x00 Index of string descriptor
describing this configuration.
7 bmAttributes Byte 0xC0 Configuration characteristics:
D7 : Reserved (set to 1) D6 :
Self-powered D5 : Remote
wakeup D4 . . . D0 : Reserved
(set to 0) (Self Powered /
RemoteWakeup UnSupport)
8 MaxPower Byte 0x31 Maximum power consumption
of this configuration. (98mA)
Offset Field Size Value Description
0 bLength Byte 0x09 Size of this descriptor in bytes.
1 bDescriptorType Byte 0x04 Interface descriptor type.
2 bInterfaceNumber Byte 0x00 Number of Interface.
3 bAlternateSetting Byte 0x00 Value used to select alternate
setting for the interface identi-
fied in the prior field.
4 bNumEndPoints Byte 0x02 Number of endpoints used by
this interface (excluding End-
point 0).
5 bInterfaceClass Byte 0x07 Class code (Printer class).