XR21B1422IL40-0A Datasheet, PDF (19/60 Pages) Exar Corporation – Enhanced 2-Ch Full-Speed USB UART

XR21B1422
USB Control Commands
The following table shows all of the USB Control Commands that are supported by the XR21B1422. Commands include
standard USB commands, CDC-ACM commands and Exar vendor specific commands. The device internal registers are
accessed using the vendor specific XR_GET_REG and XR_SET_REG, XR_GET_REVISION, XR_GET_USB_STAT and
XR_SET_USB_STAT vendor specific commands.
Table 4: Supported USB Control Commands
Name
Request
Type
Request
Value
LSB MSB
Index
LSB
MSB
Length
LSB MSB
Description
DEV GET_STATUS
0x80
IF GET_STATUS
EP GET_STATUS
0x81
0x82
DEV CLEAR_FEATURE
EP CLEAR_FEATURE
0x00
0x02
DEV SET_FEATURE
EP SET_FEATURE
0x00
0x02
SET_ADDRESS
GET_DESCRIPTOR
0x00
0x80
GET_DESCRIPTOR
0x80
GET_DESCRIPTOR
0x80
GET_CONFIGURATION
SET_CONFIGURATION
GET_INTERFACE
CDC_ACM_IF
SET_LINE_CODING
0x80
0x00
0x81
0x21
CDC_ACM_IF
GET_LINE_CODING
0xA1
CDC_ACM_IF
SET_CONTROL_
LINE_STATE
CDC_ACM_IF
SEND_BREAK
0x21
0x21
XR_GET_CHIP_ID
0xC0
0x0
0x0
0x0
0x1
0x1
0x3
0x3
0x5
0x6
0x6
0x6
0x8
0x9
0x10
0x20
0x21
0x22
0x23
0xFF
0x0
0x0
0x0
0x1
0x0
0x1
0x0
addr
0x0
0x0
0x0
0x0
n
0x0
0x0
0x0
0x0
val
LSB
0x0
0x0
0x0
0x0
0x0
0x0
0x0
0x0
0x0
0x1
0x2
0x3
0x0
0x0
0x0
0x0
0x0
0x0
val
MSB
0x0
0x0
0x0
0x2
0x0
0x0
0x0,0x4, 0x0
0x84
0x0
0x0
0x0,0x4, 0x0
0x84
0x0
0x0
0x0,0x4, 0x0
0x84
0x0
0x0
0x0
0x0
LangID LangID
0x0
0x0
0x0
0x0
0x0
0x0
0x0
0x0
Chan # 0x0
0x2
0x2
0x0
0x0
0x0
0x0
0x0
len
MSB
len
MSB
len
MSB
0x1
0x0
0x1
0x7
Chan # 0x0
0x7
Chan # 0x0
0x7
Chan # 0x0
0x0
0x0
0x0
0x6
0x0
0x0
0x0
0x0
0x0
0x0
0x0
0x0
len
MSB
len
MSB
len
MSB
0x0
0x0
0x0
0x0
0x0
0x0
0x0
0x0
Device: remote wake-up + self-
powered
Interface: zero
Endpoint: halted
Device remote wake-up
Endpoint halt
Device remote wake-up
Endpoint halt
addr = 1 to 127
Device descriptor
Configuration descriptor
String descriptor
n = 0, 1
Set the UART baud rate, parity,
stop bits, etc. Channel #0, 2 for
channel A, B respectively.
Get the UART baud rate, parity,
stop bits, etc. Channel #0, 2 for
channel A, B respectively.
Set/Clear DTR in CDC-ACM
mode. Channel #0, 2 for chan-
nel A, B respectively.
Send a break for the specified
duration. Channel #0, 2 for
channel A, B respectively.
Get Exar VID (2 bytes), PID (2
bytes) and bcdDevice (2 bytes)
© 2014 Exar Corporation
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exar.com/XR21B1422
Rev 1A