NUC970 Technical Reference Manual
Publication Release Date: Dec. 15, 2015
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Revision V1.30
NUC97
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T
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CHNIC
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L
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NUA
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(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(INT_THRE), receiver threshold level reaching interrupt
(INT_RDA), line status interrupt (parity error or framing error or break interrupt) (INT_RLS), time-out
interrupt (INT_TOUT), MODEM/Wake-up status interrupt (INT_MODEM), Buffer error interrupt
(INT_BUF_ERR) and LIN receiver break field detected interrupt (INT_LIN_RX_BREAK).
The following diagram demonstrates the auto-flow control block diagram. Refer to Auto-Flow Control
section for detail description.
Figure 5.16-2 Auto Flow Control Block Diagram
5.16.4 Basic Configuration
Before using UART
, it’s necessary to configure related pins as the UART function and enable UART’s
clock.
For UART related pin configuration, please refer to the register SYS_MFP_GPBL, SYS_MFP_GPBH,
SYS_MFP_GPCL, SYS_MFP_GPCH, SYS_MFP_GPDH, SYS_MFP_GPEL, SYS_MFP_GPEH,
SYS_MFP_GPFH, SYS_MFP_GPGL, SYS_MFP_GPGH, SYS_MFP_GPHL, SYS_MFP_GPHH,
SYS_MFP_GPIL and SYS_MFP_GPIH to know how to configure related pins as the UART function.
UARTs
’ clock controlled by CLK_PCLKEN0[26:16]. For example, set UART6 (CLK_PCLKEN0[22])
high to enable clock for UART6
’s operation.
5.16.5 Functional Description
Line Function Description
5.16.5.1
The UART Controller supports fully programmable serial-interface characteristics by setting the
UA_LCR register. Software can use the UA_LCR register to program the word length, stop bit and
Tx FIFO
Parallel to Serial
TX
/CTS
Flow Control
Rx FIFO
Serial to Parallel
RX
/RTS
Flow Control
APB
BUS