NuMicro® NUC029LEE/NUC029SEE
32-bit Arm
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Cortex
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-M0 Microcontroller
Aug, 2018
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Note:
UART0 is equipped with 64 bytes FIFO. UART1/UART2 is equipped with 16 bytes FIFO.
Figure 6.13-2 UART Block Diagram
Each block is described in detail as follows:
TX_FIFO
The transmitter is buffered with a 64/16 byte FIFO to reduce the number of interrupts presented to
the CPU.
RX_FIFO
The receiver is buffered with a 64/16 byte FIFO (plus three error bits per byte) to reduce the
number of interrupts presented to the CPU.
TX shift Register
This block is the shifting the transmitting data out of serially control.
RX shift Register
This block is the shifting the receiving data in of serially control.
Modem Control 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. Refer to baud rate equation.
IrDA Encode
This block is IrDA encode control block.
IrDA Decode
This block is IrDA decode control block.
Control and Status Register
This field is register set that including the FIFO control registers (UA_FCR), FIFO status registers
(UA_FSR), and line control register (UA_LCR) for transmitter and receiver. The time-out control
register (UA_TOR) identifies the condition of time-out interrupt. This register set also includes the
interrupt enable register (UA_IER) and interrupt status register (UA_ISR) to enable or disable the
responding interrupt and to identify the occurrence of the responding interrupt. There are seven
types of interrupts, transmitter FIFO empty interrupt(THRE_INT), receiver threshold level reaching
interrupt (RDA_INT), line status interrupt (parity error or framing error or break interrupt)
(RLS_INT), time-out interrupt (TOUT_INT), MODEM/Wake-up status interrupt (MODEM_INT),
Buffer error interrupt (BUF_ERR_INT) and LIN receiver break field detected interrupt (LIN _INT).
6.13.4 Basic Configuration
The UART Controller function pins are configured in PB_MFP, PD_MFP, ALT_MFP, ALT_MFP1
and ALT_MFP2 registers.
The UART Controller clock are enabled in UART0_EN(APBCLK[16]) for UART0, UART1_EN
(APBCLK[17]) for UART1 and UART2_EN(APBCLK[18]) for UART2.
The UART Controller clock source is selected by UART_S(CLKSEL[25:24]).
The UART Controller clock prescaler is determined by UART_N(CLKDIV[11:8]).
UART Interface Controller Pin description is shown as following: