Firmware upgrade for UBLOX SARA-R410M-02B on the MKR NB 1500 #2

[zbelding]

I was just able to update a MKR NB1500 using a modified version of @steveroky method:

1. Solder USB cable as shown by @steveroky, but bridge the pads where the +5v is soldered. This bridge will supply the board with 5v from the soldered USB and enable USB on the modem.
2. Load blank sketch using regular USB with Tools/Board set to MKRZERO
3. Disconnect regular USB
4. Plug in soldered USB
5. Start EasyFlash with .dof file placed in easyflash folder
6. When it tells you to turn on the device, short the arrowed pin to ground for about .5 sec
   
   

This will simulate a pwr_on
7. Let it finish