XR21B1424 Datasheet, PDF (37/61 Pages) Exar Corporation – Enhanced 4-Ch Full-Speed USB UART

XR21B1424
CUSTOM_DRIVER (0x060) - Write Only
This register determines which device driver is used (custom or CDC driver). For proper operation, a custom driver must set
the ACTIVE bit prior to sending any of the 4 CDC_ACM commands supported by the XR21B1424.
Bit
15:1
0
Default
Description
0
Reserved
These bits are reserved and should be written as ‘0’.
0
Active
0: Informs the XR21B1424 that the standard CDC_ACM driver is being used.
1: Informs the XR21B1424 that a custom driver is being used.
SUSPEND_STATE (0x6A) - Read/Write
This register is used to set the state of GPIO pins based on the setting of the USE_SUSPEND bit in the SUSPEND_MODE
register.
Bit
15:14
13
12
11
10
9:8
7
6
5:4
3
2
Default
Description
0
Reserved
These bits are reserved and should be written as ‘0’.
0
DSR
0: When USE_SUSPEND is ’1,’ clear this bit to a ’0’
1: When USE_SUSPEND is ’1,’ set this bit to a ’1’
0
DTR
0: When USE_SUSPEND is ’1,’ clear this bit to a ’0’
1: When USE_SUSPEND is ’1,’ set this bit to a ’1’
0
RI
0: When USE_SUSPEND is ’1,’ clear this bit to a ’0’
1: When USE_SUSPEND is ’1,’ set this bit to a ’1’’
0
CD
0: When USE_SUSPEND is ’1,’ clear this bit to a ’0’
1: When USE_SUSPEND is ’1,’ set this bit to a ’1’’
0
Reserved
These bits are reserved and should be written as ‘0’.
0
RXT
0: When USE_SUSPEND is ’1,’ clear this bit to a ’0’
1: When USE_SUSPEND is ’1,’ set this bit to a ’1’
0
TXT
0: When USE_SUSPEND is ’1,’ clear this bit to a ’0’
1: When USE_SUSPEND is ’1,’ set this bit to a ’1’
0
Reserved
These bits are reserved and should be written as ‘0’.
0
RS485
0: When USE_SUSPEND is ’1,’ clear this bit to a ’0’
1: When USE_SUSPEND is ’1,’ set this bit to a ’1’
0
CTS
0: When USE_SUSPEND is ’1,’ clear this bit to a ’0’
1: When USE_SUSPEND is ’1,’ set this bit to a ’1’
© 2014 Exar Corporation
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exar.com/XR21B1424
Rev 1B