NEC PD78214 - Manual (Page 312)

283
Chapter 10 Clock Synchronous Serial Interface
10
Fig. 10-26 BSYE Operation
SCK
SB0
BSYE
9
BUSY
8 7 6
ACK
When BSYE = 1 at this point When reset operation is executed during
this period and BSYE = 0 at the falling edge
of SCK.
D2 D1 D0