Clarification on EDMA usage with LPI2C_MasterTransfer in S32K144

[padmaja]

Hi,

I am working on an S32K144 project using S32 Design Studio and SDK.

I have configured:

• LPI2C (I2C PAL)

EDMA driver initialized using EDMA_DRV_Init()

• UART for debugging

In my application, I am using the following APIs:

• I2C_MasterSendData()
• I2C_MasterReceiveData()

EDMA is initialized as part of the system, and I expected that the I2C transfers would utilize DMA automatically.

However, I would like to confirm:

1. Are the LPI2C PAL transfer APIs automatically using EDMA when EDMA is initialized, or do they operate in interrupt mode by default?
2. How can I verify whether the I2C transactions are actually being handled via DMA (EDMA) rather than CPU-driven interrupts?
3. Are there any configuration steps required to explicitly enable DMA for LPI2C transfers?
4. Which registers or debug signals should I monitor to confirm EDMA is active during transfers?

Please find my configuration summary:

• MCU: S32K144
• IDE:S32 design studio platform 3.4
• SDK version: RTM 4.0.3 
• Transfer mode: LPI2C PAL APIs
• EDMA initialized: Yes

Thank you for your support.

[Senlent]

Hi@padmaja

Q1.Are the LPI2C PAL transfer APIs automatically using EDMA when EDMA is initialized, or do they operate in interrupt mode by default?

Q2.Are there any configuration steps required to explicitly enable DMA for LPI2C transfers?

For Q1&Q2, You should choose "DMA" in I2C component; 

Q3.How can I verify whether the I2C transactions are actually being handled via DMA (EDMA) rather than CPU-driven interrupts?

Read the code directly, this needs little explanation.

Q4.Which registers or debug signals should I monitor to confirm EDMA is active during transfers?

You can try defining an interrupt callback function for the DMA channel and observe the DMA behavior through the callback function, or directly check the DMA registers. Please refer to the datasheet to get DMA register information.