TXZ Family
Serial Peripheral Interface
2019-02-28
43 / 67
Rev. 3.0
3.3.8. Communication control by trigger
In the master operation, when
[TXPIxCR1]
<TRGEN> is set to “1”, the function of the starting communication by
generating of a trigger can be used.
If "1" is set as
[TSPIxCR1]
<TRGEN>, when communication is not performed, it will be waiting for a trigger. If a
trigger is inputted, it will be automatically set to
[TSPIxCR1]
<TRXE>=1, and communication will be started.
After communication is completed, it will be automatically set to
[TSPIxCR1]
<TRXE>=0 and will be waiting for
a trigger.
When you use a trigger start function, please set it as
[TSPIxCR1]
<TRXE>=0. Moreover,
[TSPIxCR1]
<FC>=0
(continuously transferring) cannot use.
When using Trigger transfer control, please refer to Reference manual of “Product Information” to confirm which
trigger can use.
The operation of each transmission and reception is as follows.
(1)
Reception operation
A trigger is inputted, and if FIFO is not full, the receiving start and the clock will be outputted.
When FIFO is not full, reception is continued. And when FIFO is full clock output will be stopped. After
the number of transferring which set as
[TSPIxCR1]
<FC>
is completed, a clock output is stopped and
reception is terminated.
A trigger will be ignored if a trigger is inputted when FIFO is full. Moreover, error interruption is outputted
and a flag (
[TSPIxERR]
<TRGERR>) is set.
Please refer to "3.3.9.3. Error Interruption" for details.
(2)
Transmission operation
When the data is in FIFO, a trigger is inputted, the transmission start and the clock will be outputted.
When the data is in FIFO, transmission is continued. And when FIFO is empty clock output will be stopped.
After the number of transferring which set as
[TSPIxCR1]
<FC>
is completed, a clock output is stopped and
transmission is terminated.
A trigger will be ignored if a trigger is inputted when FIFO is empty. Moreover, error interruption is
outputted and a flag (
[TSPIxERR]
<TRGERR>) is set. Please refer to "3.3.9.3. Error Interruption" for
details.
(3) Receiving trigger
It receives when communication is not performed. And the trigger input under communicating is ignored.