XR21B1421 Datasheet, PDF (47/50 Pages) Exar Corporation – Enhanced 1-Ch Full-Speed

XR21B1421
Table 30: Default Pin Configuration
Pin
Default Value
Default Configuration
RX
TX
GPIO0/CLK
GPIO1/RTS#/RS485
GPIO2/CTS#
GPIO3/RS485
GPIO4/TXT
GPIO5/RXT
GPIO6/CD#
GPIO7/RI#
GPIO8/DTR#
GPIO9/DSR#
USB_STAT1
USB_STAT2
0x02
0x00
0x03
0x03
0x03
0x03
0x03
0x00
0x00
0x02
0x02
0xA
0x1A
Rx Data Input (not configurable)
Data P-P Output
GPIO Input
RTS OD Output*
CTS Input*
RS-485 half-duplex Ctrl PP
TX Toggle PP Output
RX Toggle PP Output
GPIO Input
GPIO Input
GPIO PP Output
GPIO PP Output
SUSPEND PP Output
SUSPEND# PP Output
* Although GPOI1/RTS#/RS485 and GPIO2/CTS# have RTS# and CTS# functionality by default, H/W RTS/CTS flow con-
trol must be enabled before using this function.
GET / SET_LANGID
Transfer Type: Control In / Out
Transfer Size: 3 bytes
The GET / SET_LANGID report gets or sets unicode UTF-16 Language ID. Default Language ID code is 0x0409
Field
Report ID
LANGID LSB
LANGID MSB
Offset
0
1
2
Size
1
1
1
Value
0x67
0x09
0x04
Description
Get / Set Unicode Language ID
LSB of UTF-16LE Language ID code
MSB of UTF-16LE Language ID code
© 2014 Exar Corporation
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