Duplicate MAC Addresses and Serial Numbers

Technical Support
21

Is there a way to stop while ubooting or I need to execute something like following?

adb reboot uboot
22

I would only try to use an USB to serial cable and keep enter key pressed while the vim boots up

1 Like
23

Unfortunately even if I hold ENTER, it boots Androidā€¦ However, when I was holding POWER, then pressed RESET I was presented with Android Recovery menu, so I chose Reboot to Bootloader. Looks like Iā€™m in uboot:

But now I canā€™t get out :frowning: Reboot command keeps returning me back to this nasty bootloader and Android doesnā€™t bootā€¦

Update:
Figured how to get out: from Android recovery choose to mount /system and then boot system - Android loads then.

Anyway, even though Iā€™ve seen:

This MAC address is still not present on device when it boots :frowning:

Interestingly only ethernet MAC address changes - it seems WLAN and Bluetooth addresses remains the same over reboots.

The only way I managed to successfully set up ethernet MAC address was executing following when Android was booted:

So the ethernet MAC was set, but it was reset after reboot :frowning:

24

Hi, Gytis:
Any new process on this?

May be you can try with a new MAC Address, as some invalid address may not works.

25

Well, I generated MAC address using this generator and it still does not persist :worried:

But after reboot itā€™s again random ethernet addressā€¦

26

The ethernet address is invalid.
You can try to use the mac ā€˜98:aa:fc:60:44:caā€™
Thanks.

1 Like
27

Yes, that worked! :slight_smile:

How do you know when ethernet MAC address is valid?

28

The second bit must be even. You can try to set ethaddr following below list

  • 98:EA:4F:10:DF:FD
  • 96:EA:4F:10:DF:FD
  • 94:EA:4F:10:DF:FD
  • 92:EA:4F:10:DF:FD
  • 90:EA:4F:10:DF:FD
1 Like
29

Just confirming that this method works as expected on built Ubuntu image as well :blush:

Any idea how to burn WLAN and Bluetooth MACs?

30

@Terry Any advice how to burn WLAN and Bluetooth MAC addresses?

31

You can refer to following post. But the mac wasnā€™t parsed and you need to add source code to support it on Wi-Fi module and Bluetooth library.

About Wi-Fi mac address , You can see following line.

32

Iā€™m not sure if Iā€™ve understoodā€¦ What about burning WiFi and Bluetooth MAC addresses on Ubuntu (not Android) - some sources needs to be added?

33

If you only burn WIFI and Bluetooth MAC addresses with OTP or other, Itā€™s invalid for now.
You need to modify source code to support it.
Thanks

34

Is it possible to set the MAC address in the source code so that it is different for every board and doesnt have to be changed via the uboot serial console? i.e. change something in the u-boot or kernel source code to set it. This works but it a long and difficult job for me to get to the header to put the serial connections on. Doing it in /etc/network/interfaces/eth0 is also tricky as the dhcp server gets very confused with all the mac addresses and have to do one at a time and wait between time (i have a rubbish router!). Im using ubuntu,

Can it be set to something based off part of the CPU serial number for instance?

Really want it to just be a case of burning a new image to the board via usb-c cable and not needing to get into u-boot.

thank you!

35

Hi Birty:
Another way is that the MCU on VIM2 support customizing serial number, you might intersting in:

https://docs.khadas.com/vim2/McuDevelop.html

Regarding the CPU serial number, @Terry will repsonse you.

Good day!

36

Thanks @Gouwa - that info will be useful as well! Need to get them all on a network without going board by board first ! Thanks

37

How exactly do I do that? :confused:

38

no solution for ubuntu?

39

setenv ethaddr ā€œ00:15:18:01:81:32ā€

comand setenv not foundā€¦

can you develop this idea how should I do it? because you have not described anything because the pussy has to edit something somewhere.

40

bump! anyone know?..