Data Sheet

NUC123
May 3, 2017 Page 62 of 99 Rev.2.04
NUC123 SERIES DATASHEET
Serial Peripheral Interface (SPI) 6.14
6.14.1 Overview
The Serial Peripheral Interface (SPI) applies to synchronous serial data communication and
allows full duplex transfer. Devices communicate in Master/Slave mode with 4-wire bi-direction
interface. This NuMicro
®
NUC123 series contains up to three sets of SPI controllers performing a
serial-to-parallel conversion on data received from a peripheral device, and a parallel-to-serial
conversion on data transmitted to a peripheral device. Each set of SPI controller can be
configured as a Master or a Slave device.
This controller supports variable serial clock function for special application and it also supports 2-
bit Transfer mode. The controller also supports PDMA function to access the data buffer and also
supports Dual I/O transfer mode.
6.14.2 Features
 Up to three sets of SPI controllers
 Supports Master or Slave mode operation
 Supports 2-bit Transfer mode
 Supports Dual I/O transfer mode
 Configurable bit length of a transfer word from 8 to 32-bit
 Provide separate 8-layer depth transmit and receive FIFO buffers
 Supports MSB first or LSB first transfer sequence
 Up to two slave select lines in Master mode
 Supports Byte Reorder function
 Supports configurable suspend interval in Master mode
 Variable output serial clock frequency in Master mode
 Supports PDMA transfer
 Supports 3-Wire, no slave select signal, bi-direction interface