User's Manua switch

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CHAPTER 9 SERIAL INTERFACE 10

User’s Manual U12978EJ3V0UD

158

Table 9-2. Operating Mode Settings of Serial Interface 10

(1) Operation stop mode

CSIM10 PM22 P22 PM21 P21 PM20 P20 Start Shift P22/SI10 P21/SO10 P20/SCK10

CSIE10 DIR10 CSCK10 Bit Clock Pin Function Pin Function Pin Function

0 ×××

Note 1

×

Note 1

×

Note 1

×

Note 1

×

Note 1

×

Note 1

——P22 P21 P20

Other than above Setting prohibited

(2) 3-wired serial I/O mode

CSIM10 PM22 P22 PM21 P21 PM20 P20 Start Shift P22/SI10 P21/SO10 P20/SCK10

CSIE10 DIR10 CSCK10 Bit Clock Pin Function Pin Function Pin Function

1001

Note 2

×

Note 2

011× MSB External

clock

SI10

Note 2

SO10

(CMOS output)

SCK10 input

1 0 1 Internal

clock

SCK10 output

110 1× LSB External

clock

SCK10 input

1 0 1 Internal

clock

SCK10 output

Other than above Setting prohibited

Notes 1. Can be used as port function.

2. If used only for transmission, can be used as P22 (CMOS input/output).

Remark ×: don’t care