It can be read from white label on module,its the 64 bit SN.
eg: 000Dxxxx0Dxx28xx printed on the label.
In case if you have resetted nvram variables and lost bluetooth/wifi/ethernet MACs then you need to read if from barcode.
ConnectCard for i.mx28 has four barcodes:-
The first barcode is the Module PartNumber (5000xxxx-xx)
The second barcode is the Module PCA PartNumber (5500xxxx-xx)
The third barcode is Serial Number (SW131458970)
The fourth barcode is the WiFi MAC without any “colons” (eg: 00409Dxx022F).
From WiFi MAC you can determine all MACs:
ethaddr=00:40:9D:xx:02:2E = MAC = WiFi MAC - 1
wlanaddr=00:40:9D:xx:02:2F = WLAN or WiFi MAC
eth1addr=00:40:9D:xx:02:30 = MAC_ADDR_1 = WiFi MAC + 1
btaddr=00:40:9D:xx:02:31 = Bluetooth MAC = WiFi MAC + 2
These modules will be assigned Wifi MAC address so that Ethernet and BT MACs are generated from it during production.
If module has only 3 barcodes printed on label, contact Digi Support.