Operation; Clock Synchronous Serial Interface - Panasonic MN103S User Manual

12.3 Operation

12.3.1 Operation
Serial interface 0 and 1 can be used for both clock synchronous and duplex UART serial interfaces.
12.3.2

Clock Synchronous Serial Interface

Activation Factor for Communication
Table: 12.3.1 shows activation factors for communication. At master communication, the transfer clock is gener-
ated by setting data to the serial transmission register SCnTB.
Table:12.3.1 Synchronous Serial Interface Activation Factor
Activation factor
Transmission
Master communication Set transmission data
Slave communication
Input clock after transmission
data is set
Transmission Data Buffer
The transmission data buffer, SCnTB is a buffer of reserve that stores data to load to the internal shift register.
Data to be transferred should be set to the transmission data buffer, SCnTB, to be loaded to the internal shift reg-
ister automatically.
Reception Data Buffer
The reception data buffer, SCnRB is a buffer of reserve that pushes the received data in the internal shift register.
After the communication complete interrupt SCnTIRQ is generated, all data stored in the internal shift register are
stored to the reception data buffer SCnRB automatically. SCnRB can store data up to 1 byte. SCnRB is rewritten
in every time when communication is completed, so read out data of SCnRB till the next reception is completed.
The reception data flag SCAnRXA is set to "1" after SCnTIRQ is generated. SCAnEXA flag is cleared to "0"
after SCnRB is read out.
If a start condition is fed and activation restarts during communication, the transmission data
is invalid. Set the transmission data to SCnTB again to retransmit data.
.. ..
SCnRB is rewritten every time when communication is completed. Data of SCnRB should be
read out until the next reception is completed for continuous communication.
.. ..
Reception
Set dummy data
Input clock
Serial interface 0 and 1
Transmission/Reception
Set transmission data
Input clock after transmission
data is set
Operation
Chapter 12
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