Its Alive! muwahaha (or not...)

A project log for SentriFarm

Solving a key farming problem: is it safe to harvest / spray / sow today? (+experiments with 'big' data in agriculture)

pastcomputepastcompute 05/17/2015 at 11:081 Comment

An inAir9 sx1276 module transmitting a beacon (the text "Hello World") using LoRa mode at 918 MHz, 125kHz bandwidth and spreading factor 9. Roughly equivalent to a 4800 baud modem in terms of throughput...

Driven via a BusPirate in binary SPI mode.

Next test, using the Carambola2 with OpenWRT and spidev. I have developed the SX1276 code that communicates using an SPI abstract class, with both BusPirate and Linux spidev implementations so that _should_ hopefully be quite straightforward...

Note also the signal strength in the above picture is exaggerated - when I introduced a short delay between transmissions the colour dropped right off, i.e. stopped saturating the link. Also, I turned down the gain...

Without even using proper antennas (I hooked up a 2.4G antenna) I was able to see signal on the RTL through 3 stone walls and 50m out to the road, so a good start.


I have the beacon code working on both OpenWRT using spidev, and with the bus pirate now. So on to the receiver...


wifiwaves wrote 05/19/2015 at 19:44 point

Excellent...! Good progress, guys!

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