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9 motorola spi format with spo=1, sph=0, 9 motorola spi format with spo=1, sph=0 -8, With spo=1 and sph=0 -8 – Cirrus Logic EP93xx User Manual

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23-8

DS785UM1

Copyright 2007 Cirrus Logic

Synchronous Serial Port
EP93xx User’s Guide

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23.5.9 Motorola SPI Format with SPO=1, SPH=0

Single and continuous transmission signal sequences for Motorola SPI format with SPO=1,
SPH=0 are shown in

Figure 23-6

and

Figure 23-7

.

Figure 23-6. Motorola SPI Frame Format (Single Transfer) with SPO=1 and SPH=0

Note: In

Figure 23-6

, Q is an undefined signal.

Figure 23-7. Motorola SPI Frame Format (Continuous Transfer)

with SPO=1 and SPH=0

In this configuration, during idle periods

the SCLKOUT signal is forced HIGH

SFRMOUT is forced HIGH

the transmit data line SSPTXD is arbitrarily forced LOW

when the SSP is configured as a master, the SSPCTLOE line is driven LOW, enabling

the SCLKOUT pad (active LOW enable)

when the SSP is configured as a slave, the SSPCTLOE line is driven HIGH, disabling

the SCLKOUT pad (active LOW enable).

4 to 16 bits

MS B

LS B

LS B

Q

MS B

SSPTXD

SSPOE

SSPRXD

SFRMOUT /

SFRMIN

SCLKOUT /

SCLKIN

MS B

LSB

LS B

MS B

4 to 16 bits

SSPOE (=0)

SSPRXD

SSPTXD /

SFRMOUT /

SFRMIN

SCLKOUT /

SCLKIN