Use Segger JLink USB drive as means to configure my device through a configuration file

[dragilla]

Hi,

When I plug in my NRF51 Dongle it shows up in Windows explorer as additional drive (JLINK). Can I use this medium to configure my application? Can I read a file pun on this drive in my application running on my NRF51 Dongle? I would just put a simple config file and then read the parameters inside the app.

Thanks

[dragilla]

So what would be the easiest way to pass configuration to my app? By easiest I mean most straightforward for a user of my device but also not too complicated to implement.

A mobile app communicating via Bluetooth would be great, but that would be too much of an investment for me :)

[awneil]

dragilla said:

most straightforward for a user of my device

Knowing nothing about your device or your users, that's pretty much impossible to say

dragilla said:

A mobile app communicating via Bluetooth would be great, but that would be too much of an investment for me

So how do users normally communicate with your device? Can't you use that path? What interfaces do you have available?

UART ?

NFC?

If you were happy to use the J-Link, have that write the config info into Flash?

[dragilla]

Yes, sorry. The device is independent. You just plug it in to the power socket in the wall and it does its job. Its job is communicating via ANT+ and controlling a fan connected to it. So there really is no user interaction here.

The problem is that I need a user to somehow pass some initial information to it. Basically it's 3 numbers (INTs).

As I use the dongle, USB was my first idea - let user plug it into their computer and open a CFG file.

I have UART working (one way so far, as debug)

"have that write the config info into Flash" - How? What is the scenario here from the user perspective? 

Thanks

[awneil]

dragilla said:

"have that write the config info into Flash" - How?

Not sure if the J-Link allows just a partial update, or if it will always do a full re-program

EDIT

dragilla said:

As I use the dongle

I forget - does the nRF51 dongle give you a UART-over-USB ?

Another idea:

AIUI, the J-Link does have an extensive API - maybe you could look into that?
(you'd have to study the J-Link docs and/or contact Segger about that)

[dragilla]

Yes, I get UART over USB. I will try and see what I can find in the Jlink API. Thanks

[awneil]

If you've got UART over USB, I'd have thought that'd be the simplest thing to use?

[awneil]

In fact, it looks like you might actually be able to get to the USB MSC storage of the J-Link:

https://os.mbed.com/handbook/How-mbed-works#how-the-localfilesystem-works

(assuming Segger have implemented this?)

[awneil]

There's also RTT - that can do Host-to-Target as well as Target-to-Host  

[dragilla]

Can anyone from Nordic / Segger confirm this is possible and tell me how to do it? :)