NEC mPD789426 Series, User Manual

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CHAPTER 12 SERIAL INTERFACE 20
User’s Manual U15075EJ1V0UM00
243
Figure 12-11. 3-Wire Serial I/O Mode Timing (4/7)
(vi) Slave operation (when DAP20 = 0, CKP20 = 1, SSE20 = 1)
1 2 3 4 5 6 7 8
DI7 DI6 DI5 DI4 DI3 DI2 DI1 DI0
DO7 DO6 DO5 DO4 DO3 DO2 DO1
Note 2
SCK20
SI20
Hi-Z Hi-Z
SO20
SIO20
write
SS20
INTCSI20
DO0
SIO20 write (master)
Note 1
Notes 1. The data of SI20 is loaded at the first rising edge of SCK20. Make sure that the master outputs
the first bit before the first rising of SCK20.
2. SO20 is high until SS20 rises after completion of DO0 output. When SS20 is high, SO20 is in a
high-impedance state.
(vii) Master operation (when DAP20 = 1, CKP20 = 0, SSE20 = 0)
1 2 3 4 5 6 7 8
DO7 DO6 DO5 DO4 DO3 DO2 DO1 DO0
DI7 DI6 DI5 DI4 DI3 DI2 DI1 DI0
SCK20
SO20
SI20
SIO20
write
INTCSI20