Zero 2 Pro Cannot Enter Maskrom Mode

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Hi everyone.

I was following the tutorial to enter Maskrom mode in order to flash u-boot.

I have tried different cables and different systems (macOS, Windows, Linux), but all of them cannot recognize the device.

On linux lsusb doesn’t list the device and dmesg won’t show anything.

Serial console always print out loop messages no matter I press the button or not. When SD card is inserted, the device will always boot from SD card. With my rock 5b, if you hold the Maskrom button then you should always enter Maskrom mode.

I wonder if anyone else encountered the problem. I’m starting to believe it’s a hardware issue now.

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Ok, it seems I’ve accidentally lost some components under both USB connectors…

I have managed to recover one of them but the other is lost.

Could anyone tell me what they are? There is not text on the package. They look like inductor or fuse to me but I’m not sure. I also want to know their specs.

I got to say their connection with the board is very fragile, I always keep the SBC inside its case but this still happened.

Update 1: I have soldered one back to the OTG port but still cannot enter Maskrom mode…
Update 2: They are Ferrite beads, turns out it’s in the components placement map and schematics. So now the only problem is why I cannot enter Maskrom mode. After soldering it up, pressing Maskrom button will print lots of these lines LOOP:131;USB:0;EMMC:0;READ:0;CHK:1F;READ:0;CHK:1F;READ:0;CHK:1F;SD?:20000;, and lsusb still returns nothing.
Update 3: I accidentally connected OTG_DP and OTG_DM, now it’s fixed.