Introduction
24.1 Introduction
This document is intended to provide programmers with a functional presentation of the Master/Slave
Multichannel Serial Port Interface (McSPI) module. It also provides a register description and a module
configuration example.
McSPI is a general-purpose receive/transmit master/slave controller that can interface with up to four
slave external devices or one single external master. It allows a duplex, synchronous, serial
communication between a CPU and SPI compliant external devices (Slaves and Masters).
24.1.1 McSPI Features
The general features of the SPI controller are:
•
Buffered receive/transmit data register per channel (1 word deep)
•
Multiple SPI word access with one channel using a FIFO
•
Two DMA requests per channel, one interrupt line
•
Single interrupt line, for multiple interrupt source events
•
Serial link interface supports:
–
Full duplex / Half duplex
–
Multi-channel master or single channel slave operations
–
Programmable 1-32 bit transmit/receive shift operations.
–
Wide selection of SPI word lengths continuous from 4 to 32 bits
•
Up to four SPI channels
•
SPI word Transmit / Receive slot assignment based on round robin arbitration
•
SPI configuration per channel (clock definition, enable polarity and word width)
•
Clock generation supports:
–
Programmable master clock generation (operating from fixed 48-MHz functional clock input)
–
Selectable clock phase and clock polarity per chip select.
24.1.2 Unsupported McSPI Features
This device supports only two chip selects per module. Module wakeup during slave mode operation is not
supported, as noted in McSPI Clock and Reset Management.
Table 24-1. Unsupported McSPI Features
Feature
Reason
Chip selects 2 and 3
Not pinned out
Slave mode wakeup
SWAKEUP not connected
Retention during power down
Module not synthesized with retention enabled
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Multichannel Serial Port Interface (McSPI)
SPRUH73H – October 2011 – Revised April 2013
Copyright © 2011–2013, Texas Instruments Incorporated