MPD789426 Datasheet, PDF (243/321 Pages) NEC – 8-Bit Single-Chip Microcontrollers

SS20
SIO20
write
CHAPTER 12 SERIAL INTERFACE 20
Figure 12-11. 3-Wire Serial I/O Mode Timing (4/7)
(vi) Slave operation (when DAP20 = 0, CKP20 = 1, SSE20 = 1)
SCK20
SIO20 write (master)^{Note 1}
SI20
1
2
3
4
5
6
7
8
DI7
DI6
DI5
DI4
DI3
DI2
DI1
DI0
Hi-Z
SO20
DO7
DO6
DO5
DO4
DO3
DO2
DO1
DO0
Note 2 ^Hi-Z
INTCSI20
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.
SIO20
write
(vii) Master operation (when DAP20 = 1, CKP20 = 0, SSE20 = 0)
SCK20
1
2
3
4
5
6
7
8
SO20
DO7
DO6
DO5
DO4
DO3
DO2
DO1
DO0
SI20
INTCSI20
DI7
DI6
DI5
DI4
DI3
DI2
DI1
DI0
User’s Manual U15075EJ1V0UM00
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