Datasheet

Product data sheet Rev. 1 — 19 February 2014 31 of 99

NXP Semiconductors

LPC15xx

32-bit ARM Cortex-M3 microcontroller

8.18 USART0/1/2

Remark: All USART functions are movable functions and are assigned to pins through

the switch matrix. Do not connect USART functions to the open-drain pins PIO0_22 and

PIO0_23.

Interrupts generated by the USART peripherals can wake up the part from Deep-sleep

and power-down modes if the USART is in synchronous mode, the 32 kHz mode is

enabled, or the CTS interrupt is enabled.

8.18.1 Features

• Maximum bit rates of 4.5 Mbit/s in asynchronous mode, 15 Mbit/s in synchronous

mode master mode, and 18 Mbit/s in synchronous slave mode.

• 7, 8, or 9 data bits and 1 or 2 stop bits.

• Synchronous mode with master or slave operation. Includes data phase selection and

continuous clock option.

• Multiprocessor/multidrop (9-bit) mode with software address compare.

• RS-485 transceiver output enable.

• Autobaud mode for automatic baud rate detection

• Parity generation and checking: odd, even, or none.

• Software selectable oversampling from 5 to 16 clocks in asynchronous mode.

• One transmit and one receive data buffer.

• RTS/CTS for hardware signaling for automatic flow control. Software flow control can

be performed using Delta CTS detect, Transmit Disable control, and any GPIO as an

RTS output.

• Received data and status can optionally be read from a single register

• Break generation and detection.

• Receive data is 2 of 3 sample "voting". Status flag set when one sample differs.

• Built-in Baud Rate Generator with auto-baud function.

• A fractional rate divider is shared among all USARTs.

• Interrupts available for Receiver Ready, Transmitter Ready, Receiver Idle, change in

receiver break detect, Framing error, Parity error, Overrun, Underrun, Delta CTS

detect, and receiver sample noise detected.

• Loopback mode for testing of data and flow control.

• In synchronous slave mode, wakes up the part from deep-sleep and power-down

modes.

• Special operating mode allows operation at up to 9600 baud using the 32 kHz RTC

oscillator as the UART clock. This mode can be used while the device is in

Deep-sleep or Power-down mode and can wake-up the device when a character is

received.

• USART transmit and receive functions work with the system DMA controller.

8.19 SPI0/1

All SPI functions are movable functions and are assigned to pins through the switch

matrix. Do not connect SPI functions to the open-drain pins PIO0_22 and PIO0_23.