xr21b1411 Exar Corporation, xr21b1411 Datasheet - Page 12

• Manufacturer Part Number: xr21b1411
• Description: Enhanced 1-ch Full-speed Usb Uart
• Manufacturer: Exar Corporation

XR21B1411
ENHANCED 1-CH FULL-SPEED USB UART
The internal register set of the B1411 controls the UART channel functionality, basic functionality of the FIFOs,
OTP controls, as well as registers associated with the processing of driver commands. These registers are
accessible via the USB interface using the XR_SET_REG and XR_GET_REG USB commands. Note that the
UART_ENABLE register should be used to disable the UART prior to any register write and re-enable the
UART following any single or sequence of register writes.
GPIO_CLEAR registers as well as the TX_BREAK and ERROR_STATUS registers. The UART does not need
to be disabled when writing these four registers.
A
3.0 REGISTER SET DESCRIPTION
3.1
0X20D CUSTOM_DRIVER
0XC00 UART_ENABLE
0xC0A TX_BREAK
0xC0B XCVR_EN_DELAY
0xC0C GPIO_MODE
0xC0D GPIO_DIRECTION
0xC0E GPIO_SET
0xC06
0xC07
0xC08
0xC09
0xC0F
0xC10
0x216
0x217
0x218
0x219
DDRESS
B1411 Register Map
CDC_ACM_FLOW
_CONTROL
CDC_ACM_GPIO_
MODE
CDC_ACM_GPIO_
DIRECTION
CDC_ACM_GPIO_I
NT_MASK
FLOW_CONTROL
XON_CHAR
XOFF_CHAR
ERROR_STATUS
GPIO_CLEAR
GPIO_STATUS
R
EGISTER
N
AME
B
Bit-11 Bit-10 Bit-9
IT
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
-11
B
10
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
IT
-
T
ABLE
B
IT
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
-9 B
5: B1411 R
Bit-8
IT
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
-8 B
12
Status
Break
Bit-7
Bit-7
Bit-7
IT
0
0
0
0
0
0
0
0
0
0
0
0
0
-7 B
EGISTERS
Over-
Error
Bit-6
Bit-6
Bit-6
run
Several exceptions are the GPIO_SET and
IT
0
0
0
0
0
0
0
0
0
0
0
0
0
-6 B
GPIO
GPIO
Parity
GPIO
GPIO
GPIO
GPIO
Error
Bit-5
Bit-5
Bit-5
IT
0
0
0
5
5
0
0
0
0
5
5
5
5
-5 B
Fram-
GPIO
GPIO
GPIO
GPIO
GPIO
GPIO
Error
Bit-4
Bit-4
Bit-4
ing
IT
0
0
0
4
4
0
0
0
0
4
4
4
4
-4
Polarity
Polarity
Duplex
Enable
Duplex
Enable
XCVR
XCVR
Break
GPIO
GPIO
GPIO
GPIO
GPIO
GPIO
B
Half-
Half-
Error
Bit-3
Bit-3
Bit-3
IT
0
3
3
0
3
3
3
3
-3
GPIO
GPIO
GPIO
GPIO
GPIO
GPIO
B
Bit-2
Bit-2
Bit-2
Flow Control Mode
Flow Control Mode
IT
0
2
2
0
0
2
2
2
2
Delay
-2 B
Mode Select
Mode Select
Select
Select
GPIO
GPIO
GPIO
GPIO
GPIO
GPIO
Bit-1
Bit-1
Bit-1
RX
IT
0
1
1
0
1
1
1
1
REV. 1.1.0
-1 B
GPIO
GPIO
GPIO
GPIO
GPIO
GPIO
ACTI
Bit-0
Bit-0
Bit-0
VE
TX
IT
0
0
0
0
0
0
0
-0