xr21v1412 Exar Corporation, xr21v1412 Datasheet - Page 13

• Manufacturer Part Number: xr21v1412
• Description: 2-ch Full-speed Usb Uart
• Manufacturer: Exar Corporation

REV. 1.0.0
The internal register set of the V1412 consists of 2 different types of registers: UART Manager and UART
registers. The UART Manager controls the TX, RX and FIFOs of all UART channels. The UART registers
configure and control the remaining UART channel functionality not related to the UART FIFO.
FIFO_ENABLE Registers
Enables the RX FIFO and TX FIFOs. For proper functionality, the UART TX and RX must be enabled in the
following order:
RX_FIFO_RESET and TX_FIFO_RESET Registers
Writing a non-zero value to these registers resets the FIFOs.
A
3.0 REGISTER SET DESCRIPTION
3.1
DDRESS
0X10
0X18
0X19
0x1C
0x1D
0X11
UART Manager Registers.
FIFO_ENABLE_CHx = 0x1
UART_ENABLE = 0x3
FIFO_ENABLE_CHx = 0x3
FIFO_ENABLE_CHA
FIFO_ENABLE_CHB
RX_FIFO_RESET_CHA
RX_FIFO_RESET_CHB
TX_FIFO_RESET_CHA
TX_FIFO_RESET_CHB
R
EGISTER
N
AME
.
B
Bit-7
Bit-7
Bit-7
Bit-7
T
IT
ABLE
0
0
-7
// Enable TX FIFO
// Enable TX and RX of that channel
// Enable RX FIFO
5: UART M
B
Bit-6
Bit-6
Bit-6
Bit-6
IT
0
0
-6
13
ANAGER
B
Bit-5
Bit-5
Bit-5
Bit-5
IT
0
0
-5
R
EGISTERS
B
Bit-4
Bit-4
Bit-4
Bit-4
IT
0
0
-4
B
Bit-3
Bit-3
Bit-3
Bit-3
IT
0
0
2-CH FULL-SPEED USB UART
-3
B
Bit-2
Bit-2
Bit-2
Bit-2
IT
0
0
-2
XR21V1412
B
Bit-1
Bit-1
Bit-1
Bit-1
RX
RX
IT
-1
B
Bit-0
Bit-0
Bit-0
Bit-0
TX
TX
IT
-0