Register Descriptions
1467
SPRUH22I – April 2012 – Revised November 2019
Copyright © 2012–2019, Texas Instruments Incorporated
M3 Universal Asynchronous Receivers/Transmitters (UARTs)
21.7.6 UART Fractional Baud-Rate Divisor Register (UARTFBRD), offset 0x028
The UARTFBRD register is the fractional part of the baud-rate divisor value. All the bits are cleared on
reset. When changing the UARTFBRD register, the new value does not take effect until
transmission/reception of the current character is complete. Any changes to the baud-rate divisor must be
followed by a write to the UARTLCRH register. See
for configuration details.
Figure 21-13. UART Fractional Baud-Rate Divisor Register (UARTFBRD)
31
6
5
0
Reserved
DIVFRAC
R-0
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -
n
= value after reset
Table 21-8. UART Fractional Baud-Rate Divisor (UARTFBRD) Register Field Descriptions
Bit
Field
Value
Description
31-6
Reserved
Reserved
5-0
DIVFRAC
Fractional Baud-Rate Divisor
21.7.7 UART Line Control Register (UARTLCRH), offset 0x02C
The UARTLCRH register is the line control register. Serial parameters such as data length, parity, and
stop bit selection are implemented in this register.
When updating the baud-rate divisor (UARTIBRD and/or UARTIFRD), the UARTLCRH register must also
be written. The write strobe for the baud-rate divisor registers is tied to the UARTLCRH register.
Figure 21-14. UART Line Control Register (UARTLCRH)
31
16
Reserved
R-0
15
8
7
6
5
4
3
2
1
0
Reserved
SPS
WLEN
FEN
STP2
EPS
PEN
BRK
R-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -
n
= value after reset
Table 21-9. UART Line Control Register (UARTLCRH) Field Descriptions
Bit
Field
Value
Description
31-8
Reserved
Reserved
7
SPS
UART Stick Parity Select
When bits 1, 2, and 7 of UARTLCRH are set, the parity bit is transmitted and checked as a 0. When
bits 1 and 7 are set and 2 is cleared, the parity bit is transmitted and checked as a 1.When this bit
is cleared, stick parity is disabled.
6-5
WLEN
UART Word Length
The bits indicate the number of data bits transmitted or received in a frame as follows:
0x0
5 bits (default)
0x1
6 bits
0x2
7 bits
0x3
8 bits
4
FEN
UART Enable FIFOs
0
The FIFOs are disabled (Character mode). The FIFOs become 1-byte-deep holding registers.
1
The transmit and receive FIFObuffers are enabled (FIFOmode).