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XR21B1420 Datasheet, PDF (45/60 Pages) Exar Corporation – Enhanced 1-Ch Full-Speed USB UART
XR21B1420
Bit
3
2
1:0
Default
Description
0
REMOTE_WAKE_EN
This bit advertises if remote wakeup is enabled or disabled in D5 of bmAttributes field of the configuration
descriptor if the REMOTE_WAKE_VALID bit is set.
0: Remote wakeup is disabled
1: Remote wakeup is enabled
0
REMOTE_WAKE_VALID
This bit allows the remote wakeup setting in REMOTE_WAKE_EN to be advertised in D5 of the bmAttributes
field of the configuration descriptor.
0: Do not advertise remote wakeup setting in REMOTE_WAKE_EN
1: Advertise remote wakeup setting in REMOTE_WAKE_EN
0
POWER_MODE
This field determines power mode as reported in the configuration descriptor.
00: Bus powered mode
01: Self powered mode
10: Self powered mode
11: Invalid
RELEASE_MAJOR (0x018) - Read/Write OTP
Bit
7:0
Default
0
Major Release
Description
RELEASE_MINOR (0x019) - Read/Write OTP
Bit
7:0
Default
0
Minor Release
Description
AUTO_FLUSH (0x01A) - Read/Write OTP
This register controls whether the FIFO buffers are flushed on open and/or close events.
Bit
7:5
4
3
Default
Description
0
Reserved
These bits are reserved and should be written as ‘0’.
0
RX_CLOSE
0: Do not automatically flush the RX FIFO
1: Automatically flush the RX FIFO when the COM port is closed
0
RX_OPEN
0: Do not automatically flush the RX FIFO
1: Automatically flush the RX FIFO when the COM port is opened
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