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CHAPTER 16 SERIAL INTERFACE IICA
User’s Manual U19780EJ2V0UD
442
16.4 I
2
C Bus Mode Functions
16.4.1 Pin configuration
The serial clock pin (SCLA0) and serial data bus pin (SDAA0) are configured as follows.
(1) SCLA0 .... This pin is used for serial clock input and output.
This pin is an N-ch open-drain output for both master and slave devices. Input is Schmitt input.
(2) SDAA0 .... This pin is used for serial data input and output.
This pin is an N-ch open-drain output for both master and slave devices. Input is Schmitt input.
Since outputs from the serial clock line and the serial data bus line are N-ch open-drain outputs, an external pull-up
resistor is required.
Figure 16-12. Pin Configuration Diagram
Master device
Clock output
(Clock input)
Data output
Data input
V
SS
V
SS
V
DD
V
DD
(Clock output)
Clock input
Data output
Data input
V
SS
V
SS
Slave device
SCLA0
SDAA0
SCLA0
SDAA0