Operation Flowcharts - Fujitsu FR60 Hardware Manual

2
CHAPTER 15 I C INTERFACE
15.4

Operation Flowcharts

This section provides operation flowcharts using slave address, data transfer, and
receive data as examples.
■ Example of Slave Address and Data Transfer
Figure 15.4-1 is an example of slave address and data transfer.
7-bit slave addressing
Start
BER bit clear (set)
Interface enable EN=1
IDAR=S. address <<1+RW
MSS=1 INT=0
N
INT=1?
Y
Y
BER=1?
N
Y
AL=1?
N
ACK?
(LRB=0?)
Y
Preparing for
data transfer
Transfer completed
- The slave does not generate
ACK, or the master cannot
receive ACK.
- First set EN to "0" then perform
retransmission.
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Figure 15.4-1 Example of Slave Address and Data Transfer
Restart and transfer
due to check of AAS
N
Transfer data
Start
Slave address in
write access
IDAR = Byte data
INT=0
N
INT=1?
Y
Y
BER=1?
Bus error
N
Y
Restart and transfer
AL=1?
due to check of AAS
N
ACK?
N
(LRB=0?)
Y
Y
Transfer
of last
byte
N
Transfer completed
- Generate a repeated START
condition or STOP condition.
- Check that a STOP condition
has been generated (BB = 0),
and set EN to "0".
Transfer completed
Transmission:
- The slave does not generate
ACK, or the master cannot
receive ACK.
- Set EN to "0" for retransmission.
Reception:
Generate a repeated START
condition or STOP condition
without acknowledge.