LM3S5737 Datasheet, PDF (494/833 Pages) Texas Instruments – Stellaris® LM3S5737 Microcontroller

Universal Asynchronous Receivers/Transmitters (UARTs)
13.1 Block Diagram
Figure 13-1. UART Module Block Diagram
System Clock
DMA Request
Interrupt
Identification
Registers
UARTPCellID0
UARTPCellID1
UARTPCellID2
UARTPCellID3
UARTPeriphID0
UARTPeriphID1
UARTPeriphID2
UARTPeriphID3
UARTPeriphID4
UARTPeriphID5
UARTPeriphID6
UARTPeriphID7
DMA Control
UARTDMACTL
Interrupt Control
UARTIFLS
UARTIM
UARTMIS
UARTRIS
UARTICR
UARTDR
Control/Status
UARTRSR/ECR
UARTFR
UARTLCRH
UARTCTL
UARTILPR
TxFIFO
16 x 8
.
.
.
Baud Rate
Generator
UARTIBRD
UARTFBRD
RxFIFO
16 x 8
.
.
.
Transmitter
(with SIR
Transmit
Encoder)
Receiver
(with SIR
Receive
Decoder)
UnTx
UnRx
13.2
Signal Description
Table 13-1 on page 494 lists the external signals of the UART module and describes the function of
each. The UART signals are alternate functions for some GPIO signals and default to be GPIO
signals at reset, with the exception of the U0Rx and U0Tx pins which default to the UART function.
The column in the table below titled "Pin Assignment" lists the possible GPIO pin placements for
these UART signals. The AFSEL bit in the GPIO Alternate Function Select (GPIOAFSEL) register
(page 371) should be set to choose the UART function. For more information on configuring GPIOs,
see “General-Purpose Input/Outputs (GPIOs)” on page 348.
Table 13-1. UART Signals (100LQFP)
Pin Name
Pin Number Pin Type Buffer Type^a Description
U0Rx
26
I
TTL
UART module 0 receive. When in IrDA mode, this signal has
IrDA modulation.
U0Tx
27
O
TTL
UART module 0 transmit. When in IrDA mode, this signal has
IrDA modulation.
a. The TTL designation indicates the pin has TTL-compatible voltage levels.
494
November 17, 2011
Texas Instruments-Production Data