Fanstel USB840 Set Vdd from 1.8 to 3.3

[Prathik]

Hi. I have been using this document to work on the Fanstel USB840F device.
USB840F_User_Manual (squarespace.com) 

After erasing the device, I could'nt run this below command

Please let me know what I can do to make it work.Thank you

[ketiljo]

You probably have a programmer/debugger that can't handle 1.8V? Connect 3.0 V to VDD temporarily so that you can set this register, 

[Prathik]

Thank you for your response Ketiljo. I use Fanstel Dongle BT840.  Is it possible to do it for this device.

I use JLink EDU programmer.

[ketiljo]

According to the schematic,  https://www.fanstel.com/s/USB840F-V6.pdf, the VDD pin is accessible at JS1. Connect this to an external 3 V supply  and you should be able to set the regulator to 3.3 V with your programmer. Do not connect USB at the same time!