Recovering Bootloader/SPL for NetBotz 755

[MarkusLL]

Hello everyone,

I am trying to restore a bricked APC NetBotz 755 unit.

Current state: The device fails to boot from the SD card. The serial console output repeats the following message: "Trying to boot from SPI"

This indicates that the BootROM is skipping the SD card (likely due to a missing or corrupted A2 partition) and attempting to find a bootloader in the SPI Flash, which also seems to be empty or corrupted.

What I have: I have the official firmware update files extracted from the .sedp package:

1. soc_system.rbf / ecp_fpga_firmware_bestla2G.rbf (FPGA images)

2. kern.img (FAT16 partition image with zImage and DTB)

3. root.img (RootFS image)

The problem: The official update package does not contain the Preloader (SPL) or U-Boot binaries (u-boot-with-spl.sfp). It seems APC assumes the bootloader is already present in the SPI Flash or on the factory SD card. My original SD card is corrupted, and I cannot retrieve the first sectors (Partition Type 0xA2).

What I am looking for: Does anyone have a raw dump of the boot partition or the u-boot-with-spl.sfp file specifically for the NetBotz 750/755 platform?

Any help or direction on where to find the recovery image for this specific board would be greatly appreciated.

Thank you!

[Cory_McDonald]

Hello @MarkusLL,

In a case such as this, I would recommend reaching out to technical support to see if there is any recovery steps that can be taken or to look into warranty options.  Direct SD card access for NetBotz 755 usually is not a recovery method, but they can look into if there are any available options for you from an official SE standpoint.

Kind Regards,

Cory