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NUC126
Aug. 08, 2018
Page
857
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Rev 1.03
NUC12
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Each block is described in detail as follows:
TX_FIFO
The transmitter is buffered with a 16 bytes FIFO to reduce the number of interrupts presented to the
CPU.
RX_FIFO
The receiver is buffered with a 16 bytes FIFO (plus three error bits, BIF (UART_FIFOSTS[6]), FEF
(UART_FIFOSTS[5]), PEF (UART_FIFOSTS[4])) to reduce the number of interrupts presented to the
CPU.
TX Shift Register
This block is responsible for shifting out the transmitting data serially.
RX Shift Register
This block is responsible for shifting in the receiving data serially.
Modem Control and Status Register
This register controls the interface to the MODEM or data set (or a peripheral device emulating a
MODEM).
Baud Rate Generator
Divide the external clock by the divisor to get the desired baud rate clock. Refer to baud rate equation.
IrDA Encode
This block is IrDA encoding control block.
IrDA Decode
This block is IrDA decoding control block.
FIFO & Line Control and Status Register
This field is register set that including the FIFO control register (UART_FIFO), FIFO status register
(UART_FIFOSTS), and line control register (UART_LINE) for transmitter and receiver. The time-out
register (UART_TOUT) identifies the condition of time-out interrupt.
Auto-Baud Rate Measurement
This block is responsible for auto-baud rate measurement.
Interrupt Control and Status Register
There are ten types of interrupts, Receive Data Available Interrupt (RDAINT), Transmit Holding
Register Empty Interrupt (THERINT), Transmitter Empty Interrupt (TXENDINT), Receive Line Status
Interrupt (parity error or framing error or break interrupt) (RLSINT), MODEM Status Interrupt
(MODEMINT), Receiver Buffer Time-out Interrupt (RXTOINT), Buffer Error Interrupt (BUFERRINT),
LIN Bus Interrupt (LININT), Wake-up Interrupt (WKINT) and Auto-Baud Rate Interrupt (ABRINT).
Interrupt enable register (UART_INTEN) enable or disable the responding interrupt and interrupt status
register (UART_INTSTS) identifying the occurrence of the responding interrupt.
Interrupt
Description
RDAINT
Receive Data Available Interrupt.
THERINT
Transmit Holding Register Empty Interrupt.
TXENDINT
Transmitter Empty Interrupt.
RLSINT
Receive Line Status Interrupt (parity error or frame error or break error).
MODEMINT
MODEM Status Interrupt.
RXTOINT
Receiver Buffer Time-out Interrupt.
BUFERRINT
Buffer Error Interrupt.