S32K312 IIC CONFIG

[chenyh]

I want to know what exactly the configuration of IIC in the box represents, and now I don't know how to modify it, and then why the SCL of IIC should be configured as the input and output mode. I remember that under normal circumstances, SCL only needs to configure the output mode, I hope someone can give me an answer, thank you very much

[RomanVR]

Hi @chenyh

The timing parameters that you're watching in configuration tools are required for the proper operation of the LPI2C controller accordingly to the operation mode.

Firstly, the preescaler is a frequency adjustable divisor to divide the module's operation clock frequency and. It can take a value of 1, 2, 4, 8, 16, 32, 64 and 128.

Find attached the table from section 71.7.1.13 Controller Clock Configuration 0 of S32K3xx Reference Manual, Rev. 9 where these timing parameters are explained.

I also attach Table 462 of section 71.6 of S32K3xx Reference Manual, Rev. 9 which includes some examples of timing configurations for different I2C operations modes:

About SCL modes, although normally SCL line is used as unidirectional, some slave devices have the need to hold the clock line low in order to tell the master to wait until the information received is processed, therefore the need of a bidirectional SCL line.

For more detailed information please refer to S32K3xx Reference Manual, Rev. 9 available at S32K3 Microcontrollers for Automotive General Purpose.

If you have more doubts, feel free to share them.

- RomanVR.