Datasheet

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Transmitter
M M
Data Type
Slave Address Reg Address Write Data
R0002-01
M: Master Device S: Slave Device
St: Start Condition W: Write ACK: Acknowledge Sp: Stop Condition
M M S M
St W ACK Sp
S
ACK
MS
ACK
R0002-02
M: Master Device S: Slave Device St: Start Condition
Sr: Repeated Start Condition ACK: Acknowledge Sp: Stop Condition NACK: Not Acknowledge
W: Write R: Read
Transmitter
M M M S
Data Type
St Slave Address W ACK
M
Reg Address
M
Sr
M
Slave Address
S
ACK
M
R
S
ACK
M
Sp
M
NACK
S
Read Data
PCM1870
SLAS544A – MAY 2007 – REVISED SEPTEMBER 2007
Write Operation
A master can write any PCM1870 registers using single access. The master sends a PCM1870 slave address
with a write bit, a register address, and the data. When undefined registers are accessed, the PCM1870 does not
send an acknowledgement. The Figure 21 shows a diagram of the write operation.
Figure 21. Framework for Write Operation
Read Operation
A master can read the PCM1870 register. The value of the register address is stored in an indirect index register
in advance. The master sends a PCM1870 slave address with a read bit after storing the register address. Then
the PCM1870 transfers the data which the index register points to. Figure 22 shows a diagram of the read
operation.
NOTE: The slave address after the repeated start condition must be the same as the previous slave address.
Figure 22. Read Operation
22 Submit Documentation Feedback Copyright © 2007, Texas Instruments Incorporated
Product Folder Link(s): PCM1870