XR21B1420IL28-0A Datasheet, PDF (56/60 Pages) Exar Corporation – Enhanced 1-Ch Full-Speed USB UART

XR21B1420
SUSPEND_MODE_MSB (0x031) - Read/Write OTP
This register configures the mode of the GPIO pins during suspend state. Note that RX and TX data pins are not controlled
by SUSPEND_STATE. USE_SUSPEND is not a physical pin, but instead acts as the control for pins in the suspended state
and is in the most significant bit position of SUSPEND_MODE_MSB.
Bit
7
6
5:4
3
2
1
0
Default
Description
0
GPIO9/RXT
0: Corresponding GPIO is push-pull output during suspend if USE_SUSPEND = ’1’
1: Corresponding GPIO is open-drain output during suspend if USE_SUSPEND = ’1’
0
GPIO8/TXT
0: Corresponding GPIO is push-pull output during suspend if USE_SUSPEND = ’1’
1: Corresponding GPIO is open-drain output during suspend if USE_SUSPEND = ’1’
0
Not used
0
GPIO7/RS485
0: Corresponding GPIO is push-pull output during suspend if USE_SUSPEND = ’1’
1: Corresponding GPIO is open-drain output during suspend if USE_SUSPEND = ’1’
0
GPIO4/CTS#
0: Corresponding GPIO is push-pull output during suspend if USE_SUSPEND = ’1’
1: Corresponding GPIO is open-drain output during suspend if USE_SUSPEND = ’1’
0
GPIO5/RTS#/RS485
0: Corresponding GPIO is push-pull output during suspend if USE_SUSPEND = ’1’
1: Corresponding GPIO is open-drain output during suspend if USE_SUSPEND = ’1’
0
GPIO6/CLK
0: Corresponding GPIO is push-pull output during suspend if USE_SUSPEND = ’1’
1: Corresponding GPIO is open-drain output during suspend if USE_SUSPEND = ’1’
SUSPEND_MODE_LSB (0x032) - Read/Write OTP
This register configures the state of the GPIO pins during suspend state.
Bit
7
6
5
4
Default
Description
0
USE_SUSPEND
0: Corresponding GPIO is push-pull output during suspend if USE_SUSPEND = ’1’
1: Corresponding GPIO is open-drain output during suspend if USE_SUSPEND = ’1’
0
Not used
0
GPIO2/DSR#
0: Corresponding GPIO is push-pull output during suspend if USE_SUSPEND = ’1’
1: Corresponding GPIO is open-drain output during suspend if USE_SUSPEND = ’1’
0
GPIO3/DTR#
0: Corresponding GPIO is push-pull output during suspend if USE_SUSPEND = ’1’
1: Corresponding GPIO is open-drain output during suspend if USE_SUSPEND = ’1’
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