[chbot] LoRa boards, and Monday's extravaganza :)

[Mark Atherton]

Just in case you haven't been following today's adventure, I managed to 
brick a "SparkFun SAMD21 Pro RF" LoRa board, by loading some demo code. 
Basically, the bootloader got clobbered.

Reasons still elude me exactly how this happened, and according to 
several forums, it is quite a popular mode of failure.

Lots of work later, a replacement binary was found for the bootloader, 
and some effort was put into trying to locate path-of-least-resistance 
in terms of a programmer.

To cut a long story short, the SF board does have the two SWD pins 
exposed, but to a pair of tiny and fragile (1.5mm) pads. And as you have 
probably figured out by now, one of them broke off having been soldered to.

During this adventure, I had a chance to explore the competing product 
by AdaFruit. This unit appears to be much better supported, and even has 
a header for JTAG/SWD, as well as a how-to about reloading the bootloader.

So lessons have been learned, and I think that having a properly exposed 
programming interface needs to be added to the shopping list when 
exploring new hardware.


On a related subject, we are lucky enough to have two speakers tomorrow 
evening talking about LoRa, one on The Things Network, the other about a 
private wireless network.

Hope to see you there.

Regards, Mark