I have a project of producing 100 to 500 nodes based on this open source board (with some modifications)
http://www.rocketscream.com/blog/product/mini-ultra-pro-with-radio/ (RFM95w)
I managed to get a quote of 18 USD per unit, built, soldered, tested.
Before I start , I would like to know if ARM Cortex M0+ is working with TTN ?
Your question is ambiguous. Do you mean to ask that the M0+ variant has the correct connections to interface with the RFM95w or do you mean to ask if there is a software stack running on the M0+ that will allow this device to work as a LoRaWAN node?
Hardware wise, SPI and a few GPIO is all it needs to drive the RFM95w.
For the software, it depends on the M0+ chip selected. Does it have enough flash and ram for the protocol stack and is there enough to actually implement a useful device?
These are the sort of things that would have been sorted and prototyped before designing a PCB and getting quotes for something that you don’t know if it will actually work!
Hope this helps
Andrew
Yes I was not clear , you’re right
I’m not worrying about the hardware compatibility. I’ve checked this before
Just want to save time on the coding (the ARM will be flashed with arduino image) to work with TTN.
My question was : Any one tested a node software to be compatible with TTN on a cortex M0+ before ?
Several reports here of people who got the Adafruit M0 feather working with RFM95 which may be similar to what you have (just saying Cortex M0+ isn’t really enough)
Thanks much jmaecelino. I’ll dig more. Just wanted not to invest 2000 EUR in a first batch. Your orientation sound careful. I will make a proto first to get sure. Although my researches on this unit are saying it is ok.
I do have the Semtech and LMIC stacks running on STM32 L073 and L152 STM chips running like a charm on TTN network, both in MBed or native variant.
Most of the modules are built around Cortex core.