STM32N6570-DK – Ethernet TX Failure & Camera Frame Not Received

[Selvarasu_K]

The FSBL → Application jump is working fine, and the application is running properly from external flash.

However, I am facing the following issues:

Ethernet Issue

• Ethernet initialization is successful
• PHY link is UP, but speed is 10 Mbps (Full Duplex)
• Ping is not working
• Ethernet TX is failing continuously
• No UDP data transmission

Camera Issue

• Camera (IMX335) is detected over I2C
• Initialization is successful
• Streaming is started
• But no frame data is received (first frame timeout)

Support Required

• How to fix Ethernet bring-up (speed, ping, TX issue)
• Any example/project for Ethernet + UDP communication
• Guidance for CSI/DCMIPP camera interface and how to read frame data
  
  The suggested VENC_RTSP_Server example contains only initialization; full configuration and setup details are not clear & .ioc also missing

These issues are blocking further progress. Kindly provide guidance or reference examples.

[STackPointer64]

Hello @Selvarasu_K,

I suggest running each example individually before integrating them into the same project, as it becomes more confusing to debug both issues at once.

For the Ethernet part, I suggest creating a separate project and inspecting and comparing the configuration of the NX_UDP_Echo_Server project available in the example selector. Just make sure you adapt the Ethernet pinout to your board schematics. To make this easier, you can use an application such as WinMerge.

As for camera capture, you could do the same with the VENC_SDCard example.

Best regards,

[Selvarasu_K]

Dear ST Support Team,

Thank you for your suggestion to refer to the NX_UDP_Echo_Server example and compare configurations.

I have tried to follow your recommendation, but I am still facing issues with Ethernet bring-up. Please find my observations and current status below.

---

1. Current Status (My Application Logs)

• ETH HAL initialization is successful

• PHY link is coming UP

• However, it is negotiating only at 10 Mbps (Full Duplex) instead of 100 Mbps

• MAC is configured accordingly (10M Full)

• Transmission is working (ARP packets are being sent successfully)

• Reception is not working at all

Key observations from logs:

• ARP requests are transmitted:

  • "ETH Tx OK len=42"

• But:

  • No RX frames received

  • RX descriptors remain unused (OWN bit = 0)

  • Frames processed = 0

• Ping from PC is failing (Destination unreachable / timeout)

---

2. Ping Result

PC Configuration:

• IP: 10.0.0.100

• Subnet: 255.255.255.0

Result:

• No successful ping response

• Board keeps sending ARP requests but does not receive any response

---

3. NX_UDP_Echo_Server Example Issue

I tried to use the NX_UDP_Echo_Server example as suggested, but I am facing the following challenges:

• The example does not contain complete project structure:

  • No FSBL / Application split

  • Unable to directly build and flash on my board

• The example mainly includes:

  • Peripheral initialization (Ethernet init)

  • But no clear IP configuration / MAC handling / UDP logic visible

Due to this:

• I am unable to use it effectively as a reference

• I cannot directly run or debug the example on my hardware

---

4. Request for Support

I am currently stuck at Ethernet bring-up stage. I kindly request your support on the following:

1. Could you please share a complete working Ethernet example project (buildable & flashable) for STM32N6570-DK?

   • Including proper initialization

   • PHY + MAC configuration

   • IP setup

   • Basic ping or UDP working demo

2. Based on my logs:

   • PHY link is UP

   • TX is working

   • RX is not working

   Could you guide:

   • What could cause RX path to completely fail?

   • Why RX descriptors are not being updated (OWN bit remains 0)?

3. Also, PHY is falling back to 10 Mbps:

   • Could this be due to RGMII delay configuration or clock issue?

   • Any recommended configuration for this board?

---

I have already verified:

• DMA descriptor placement (non-cacheable region)

• PHY address

• Basic initialization flow

But still unable to receive any Ethernet frames.

---

Kindly help me with a working reference or specific guidance to resolve this issue.

Thank you for your support.

Best regards,
Selvarasu K