NEC 78014Y Series User Manual page 443

(5) Automatic data transmit/receive interval
When the automatic data transmit/receive function is used, one byte is transmitted/received and then the read/
write operations from/to the buffer RAM are performed, therefore an interval is inserted before the next data
transmission/reception.
When the automatic data transmit/receive function is performed by an internal clock, since the read/write
operations from/to the buffer RAM are done in parallel with CPU processing, the interval depends on the CPU
processing at the moment of serial clock's eighth rising-edge timing.
When the automatic data transmit/receive function is performed by an external clock, it must be chosen so that
the interval may be longer than the value shown in (b).
CSIIF1
CSIIF1: Interrupt request flag
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CHAPTER 17 SERIAL INTERFACE CHANNEL 1
Figure 17-22. Automatic Data Transmit/Receive Interval
SCK1
SO1 D7 D6 D5 D4 D3 D2 D1 D0
SI1 D7 D6 D5 D4 D3 D2 D1 D0
Interval
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
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