User`s manual

SPI Port
CS485xx Hardware User’s Manual
DS734UM7 Copyright 2009 Cirrus Logic, Inc. 3-16
Figure 3-14. SPI Address and Data Bytes
3.3.1.1.1 SCP_BSY Behavior
The SCP_BSY signal is not part of the SPI protocol, but it is provided so that the slave can signal to the
master that it cannot receive any more data. A falling edge of the SCP_BSY
signal indicates the master must
halt transmission. Once the SCP_BSY
signal goes high, the suspended transaction may continue. The host
must obey the SCP_BSY
pin or control data will be lost.
SCP_CLK
S
CP_MOSI 7-bit SPI Address Data Byte
SCP_CS
R/W
SCP_CLK
S
CP_MOSI
Data Byte
SCP_CS
S
CP_MISO
R/W7-bit SPI Address
SCP_CLK
S
CP_MOSI 7-bit SPI Address Data Byte
SCP_CS
R/W
SCP_CLK
S
CP_MOSI
Data Byte
SCP_CS
S
CP_MISO
R/W7-bit SPI Address
SCP_CLK
S
CP_MOSI 7-bit SPI Address Data Byte
SCP_CS
R/W
SCP_CLK
S
CP_MOSI
Data Byte
SCP_CS
S
CP_MISO
R/W7-bit SPI Address