Enhanced Universal Serial Communication Interfaces (eUSCI_A, eUSCI_B) Overview
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SLAU367P – October 2012 – Revised April 2020
Copyright © 2012–2020, Texas Instruments Incorporated
Enhanced Universal Serial Communication Interface (eUSCI) – SPI Mode
31.1 Enhanced Universal Serial Communication Interfaces (eUSCI_A, eUSCI_B) Overview
Both the eUSCI_A and the eUSCI_B support serial communication in SPI mode.
31.2 eUSCI Introduction – SPI Mode
In synchronous mode, the eUSCI connects the device to an external system through three or four pins:
UCxSIMO, UCxSOMI, UCxCLK, and UCxSTE. SPI mode is selected when the UCSYNC bit is set, and
SPI mode (3-pin or 4-pin) is selected with the UCMODEx bits.
SPI mode features include:
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7-bit or 8-bit data length
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LSB-first or MSB-first data transmit and receive
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3-pin and 4-pin SPI operation
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Master or slave modes
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Independent transmit and receive shift registers
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Separate transmit and receive buffer registers
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Continuous transmit and receive operation
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Selectable clock polarity and phase control
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Programmable clock frequency in master mode
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Independent interrupt capability for receive and transmit
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Slave operation in LPM4
shows the eUSCI when configured for SPI mode.