XR21B1420 Datasheet, PDF (37/60 Pages) Exar Corporation – Enhanced 1-Ch Full-Speed USB UART

XR21B1420
Bit
12:10
9:8
7:6
5
4:2
1
0
Default
Description
0
SEL1
000: USB_STAT2 asserted high when in suspended state or when USB bus reset is asserted
001: USB_STAT2 asserted high when in suspended state
010: For low power device (<= 100 mA) USB_STAT2 asserted high when in suspended state. For high power
device (101-500 mA) asserted high when in suspended state or when not yet configured.
011: USB_STAT2 asserted high when USB bus reset is asserted
100: USB_STAT2 asserted high when in suspended state or when USB bus reset is asserted
101: USB_STAT2 asserted low when in suspended state
110: For low power device (<= 100 mA) USB_STAT2 asserted low when in suspended state. For high power
device (101-500 mA) asserted low when in suspended state or when not yet configured.
111: USB_STAT2 asserted low when USB bus reset is asserted
10
CTRL1
00: Invalid
01: USB_STAT2 open drain
10: USB_STAT2 actively driven
11: Invalid
0
Reserved
These bits are reserved and should be written as ‘0’.
0
STATE0
Returns the current state of the USB_STAT1 pin.
0
SEL0
000: USB_STAT1 asserted low when in suspended state or when USB bus reset is asserted
001: USB_STAT1 asserted high when in suspended state
010: For low power device (<= 100 mA) USB_STAT1 asserted high when in suspended state. For high power
device (101-500 mA) asserted high when in suspended state or when not yet configured.
011: USB_STAT1 asserted high when USB bus reset is asserted
100: USB_STAT1 asserted low when in suspended state or when USB bus reset is asserted
101: USB_STAT1 asserted low when in suspended state
110: For low power device (<= 100 mA) USB_STAT1 asserted low when in suspended state. For high power
device (101-500 mA) asserted low when in suspended state or when not yet configured.
111: USB_STAT1 asserted low when USB bus reset is asserted
0
CTRL0
00: Invalid
01: USB_STAT1 open drain
10: USB_STAT1 actively driven
11: Invalid
Reserved
This bit is reserved and should be written as ‘0.’
© 2014 Exar Corporation
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exar.com/XR21B1420
Rev 1A