Hi NXP Team,
I'm working with the S32K3-T-BOX (S32K344, schematic SCH-50735 Rev C) and trying to get Ethernet working with the S32K344 lwIP example Example_S32K344_EMAC_lwIP_Baremetal_S32K344_v1_0_S32DS36_RTD700.
What I did
- Moved the project from the S32K3X4EVB-T172 setup to the T-Box: package S32K344_172HDQFP, 40 MHz external crystal, RMII.
- Re-routed the EMAC pins to match the T-Box schematic: TXD0 PTC2, TXD1 PTD7, TX_EN PTD12, TX_CLK/REF_CLK PTD11 (input), RXD0 PTC0, RXD1 PTC1, RX_DV PTC17, RX_ER PTC14.
- The project builds with 0 errors. I flashed it with the S32 Debug Probe on the S32K344 header.
- The firmware runs through main() → device_init() → Eth_43_GMAC_Init() and stays in the main loop until the example's test timeout.
Problem The RJ45 LINK/activity LEDs never turn on, and Windows shows the adapter as "Disconnected". The same PC port and cable link normally with other devices.
Board checks
- Power LEDs (PF5020 rails) are on.
- J51, J53 and J55 are on 1-2.
- S1 is OFF/OFF (boot from SJA1110 flash).
- U36 (SJA1110 status LED) does not blink green, so I suspect the SJA1110B has no firmware or configuration.
Questions
- The example's description.txt lists only the S32K3X4EVB-T172. Is it intended to work on the S32K3-T-BOX, or only on the EVB?
- Does the SJA1110B need its own firmware or configuration (for example S32K3_T_BOX_LWIP_for_SJA1110) before the RJ45 link comes up?
- If so, what is the recommended procedure and debugger for the SJA1110 debug header (J57)? Is a prebuilt image available?
- Is any SJA1110B-side setting needed so the RMII link to the S32K344 EMAC works (RMII mode, 50 MHz REF_CLK direction)?
Thanks!
Hello @Divya2904 ,
Please find the answers to your questions below.
1. The example is intended for the S32K3X4EVB-T172 and will not run on the S32K3-T-BOX without board-specific modifications.
Please refer to slide 15 of the https://www.nxp.com/webapp/Download?colCode=TP-S32K3-T-BOX-LWIP-GUIDE In particular:
- The S32K3-T-BOX uses a 40 MHz external crystal, while the EVB uses a 16 MHz crystal. The clock configuration must therefore be updated accordingly.
- The RMII reference clock for the S32K344 EMAC is provided by the SJA1110. A short delay should be added before the S32K344 clock initialization to allow the SJA1110 to start and provide the RMII reference clock.
- The external PHY initialization in
device_init()is not required because the Ethernet PHY and switch initialization is handled by the SJA1110 firmware.
2. Yes, the SJA1110B requires its own firmware and switch configuration. Without running SJA1110 firmware, the RJ45 port and the RMII connection to the S32K344 will not be initialized.
I have prepared examples for several SJA1110-based boards, including the S32K3-T-BOX. Please refer to Ethernet Switch SJA1110 Examples. The examples initialize and test the relevant ports and provide LED indication. A prebuilt flash_image.bin is included, so rebuilding the project is not required.
Due to distribution restrictions, the complete SJA1110 example projects cannot be attached directly to the Community article. The example may be provided upon request through NXP Technical Support and may require an NDA. Please submit a support case through NXP Technical Support and reference the required S32K3-T-BOX SJA1110 example.
3. Connect a debugger that supports the SJA1110 device to the SJA1110 debug header J57 and program the provided flash image. I use either a PEmicro Multilink debugger or Lauterbach TRACE32. A prebuilt image is available as described in answer 2.
4. Yes. The SJA1110 firmware must configure the switch port connected to the S32K344 for RMII operation and provide the 50 MHz RMII reference clock to the S32K344 EMAC. This is handled by the S32K3-T-BOX-specific SJA1110 example.
The inactive U36 LED is therefore a strong indication that the SJA1110 firmware is not currently running or that the device did not boot correctly.
Best regards,
Pavel
Hi Pavel,
Thank you for the detailed answers. They confirmed the cause for us. Our status:
- The SJA1110 is powered (jumpers J51, J53, J55 on 1-2, PF5020 rails on) and S1 is OFF/OFF, but U36 stays dark.
- We built the public S32K3_T_BOX_LWIP_for_SJA1110 project to app_flash.elf.
- On the S32K344 side we have applied your three points: the 40 MHz clock configuration, a delay before the clock initialization, and removal of the PHY initialization from device_init().
Two questions:
- The article "Example SJA1110 FreeRTOS lwIP S32K3-T-BOX" only attaches Example_Availability.txt and no flash_image.bin. Could you share the prebuilt image directly, or tell us which support case to open (and whether an NDA is needed)?
- In the meantime, is the public S32K3_T_BOX_LWIP_for_SJA1110 project suitable for the T-BOX? Does its switch configuration forward frames between the RJ45 port (P1) and the S32K344 RMII port (P2)? We'd also like to confirm that a PEmicro Multilink is the right probe for J57.
Best regards, Divya
Hello @Divya2904 ,
Your DIP switches are inline with my board.
Please, check signal level of DEVICE_CFG_N connected to PTA13. If switch accepts the configuration, DEVICE_CFG_N should be low.
ad 1. Yes, due to distribution restrictions, the complete SJA1110 example projects cannot be attached directly to the Community article. The example may be provided upon request through NXP Technical Support and may require an NDA. Please submit a support case through NXP Technical Support and reference the required S32K3-T-BOX SJA1110 example.
The main reason is that Automotive Ethernet belongs to export policy control and additional approvals might be required.
ad 2. Yes, S32K3_T_BOX_LWIP_for_SJA1110 project is dedicated for the T-BOX. Yes, L2 Forwarding table has default settings - forward to all ports except to source port. Yes, I used PE micro multilink FX.
Best regards,
Pavel
Hi Pavel,
Thank you for the clarification.
I am working with the Example_S32K344_EMAC_lwIP_Baremetal_S32K344_v1_0_S32DS36_RTD700 example and have modified the EMAC pin configuration to match the S32K3-T-BOX hardware.
Could you please confirm whether the pin configuration shown in the attached S32DS ConfigTools screenshot is correct for the T-Box, or if any changes are required?
Best regards
Divya
Hello @Divya2904 ,
Your pins appear to be correct. MDIO and MDC are not required.
Best regards,
Pavel