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
SCP_MOSI
7-bit SPI Address
Data Byte
SCP_CS
R/W
SCP_CLK
SCP_MOSI
Data Byte
SCP_CS
SCP_MISO
R/W
7-bit SPI Address
SCP_CLK
SCP_MOSI
7-bit SPI Address
Data Byte
SCP_CS
R/W
SCP_CLK
SCP_MOSI
Data Byte
SCP_CS
SCP_MISO
R/W
7-bit SPI Address
SCP_CLK
SCP_MOSI
7-bit SPI Address
Data Byte
SCP_CS
R/W
SCP_CLK
SCP_MOSI
Data Byte
SCP_CS
SCP_MISO
R/W
7-bit SPI Address