Cirrus Logic CS485xx - Manual (Page 42)

Serial Control Port Configuration
CS485xx Hardware User’s Manual
DS734UM7 Copyright 2009 Cirrus Logic, Inc. 3-10
Figure 3-9. I
2
C Read Flow Diagram
SCP_IRQ
(LOW)?
BYTES READ = 4?
Y
N
N
Y
SEND I2C STOP: DRIVE
SCP_SDA HIGH WHILE
SCP_CLK IS HIGH
SCP_IRQ LOW?
Y
N
START
SEND I2C START: DRIVE
SCP_SDA LOW WHILE
SCP_CLK IS HIGH
WRITE ADDRESS BYTE
0x81
READ DATA BYTE
SEND ACK
SEND NACK
SCP_SDA ==
ACK?
Y
N
EXIT (ERROR)