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After the Touch Sensor Module is powered on, it will act as a slave device on a I2C bus. For further information about what commands could be send or receive through this interface, please refer to I2C Transport.

I2C Characteristics

The I2C interface meets the requirements of the standard I2C communication protocol with the following restrictions: SDA and SCL are mapped to I/O pins that are not “true” open-drain. When configured as open-drain, the PMOS connected between the I/O pin and VDD is disabled, but is still present.

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PIN 3 can be used as an interrupt input or it can be read repeatedly by the host. When the pin is set to high, the FW will wait for the host to read data from the I2C bus. When the read transaction is finished, this Data Ready signal will be reset automatically by the sensor module. The following figure shows the timing behavior of a typical I2C transaction:

I2C Reading Sequence

See .I2C Transport v2.3.

Power On and Boot Sequence

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