topic Re: S32K148 LPUART DMA RX Idle line Issue in S32K

S32K148 LPUART DMA RX Idle line Issue

Pratap_Metharamitta — Wed, 26 Mar 2025 23:56:28 GMT

Hello,

When we are trying to use the S32K148 LPUART driver to setup DMA RX Idle line we are getting RXEDGIF interrupt, we never getting IDLE.

Here our DMA buffer size is 128 bytes, and our packets are 5 bytes to 78 bytes that is why we need Idle line interrupt to handle any packet.

Please let me know if there is similar issue or share the example code if you have any.

regards, Pratap

Re: S32K148 LPUART DMA RX Idle line Issue

Senlent — Thu, 27 Mar 2025 03:28:29 GMT

Hi@Pratap_Metharamitta

This is a demo I made before. You can refer to it. I need to inform you that our SDK does not support this feature. This is just a test demo I modified myself. We will not provide more support for this. Please evaluate it yourself.

https://community.nxp.com/t5/S32K-Knowledge-Base/S32K1xx-Lpuart-IDLE-detected-with-DMA-transfer/ta-p/1945182

Re: S32K148 LPUART DMA RX Idle line Issue

Pratap_Metharamitta — Thu, 27 Mar 2025 04:09:45 GMT

Root Cause is: In the SDK LPUART driver, when enter to the LPUART_DRV_IRQHandler() all ERROR status is cleared by LPUART_DRV_ErrIrqHandler(), the FEATURE_LPUART_STAT_REG_FLAGS_MASK (in file S32K148_features.h), is 0xC01FC000U, the idle flag being clear here.

Solution: Modeling the FEATURE_LPUART_STAT_REG_FLAGS_MASK (in file S32K148_features.h), from 0xC01FC000U to 0xC00FC000U.

Please let me know can we solve this issue by above modification.