Cirrus Logic CS4970x4 - Manual (Page 63)

2-17 Copyright 2013 Cirrus Logic, Inc. DS810UM6
I2C Port
CS4953x4/CS4970x4 System Designer’s Guide
Figure 2-15. I
2
C Read Flow Diagram
SCP1_IRQ
(LOW)?
BYTES READ = 4?
Y
N
N
Y
SEND I2C STOP: DRIVE
SCP1_SDA HIGH WHILE
SCP1_CLK IS HIGH
SCP1_IRQ LOW?
Y
N
START
SEND I2C START: DRIVE
SCP1_SDA LOW WHILE
SCP1_CLK IS HIGH
WRITE ADDRESS BYTE
0x81
READ DATA BYTE
SEND ACK
SEND NACK
SCP1_SDA ==
ACK?
Y
N
EXIT (ERROR)