Category Archives: RFM69

RFM69HW transceiver now available

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Finally it’s here, the high power version of the RFM69W FSK transceiver is now available in the store!

This is a relatively new transceiver from HopeRF, suggested replacement for RFM12B, RFM22B going forward. Some rumors have gone around that those transceivers might be phased out, but HopeRF has told me there are no such plans, however they do “recommend the RFM69 in place of RFM12B/RFM22B for new designs”.

Based on my range tests, and on some feedback, these might be an ideal RF platform for RC controlled drones, even the RFM69W should give you a pretty long range, especially in open air.

RFM69HW

The RFM69HW is a 20dBm output power transceiver. In my open-air range tests I ran out of space at around 370m with this one. So potentially these will go significantly farther. The tests were done with my Gateway/Node example sketches, at 55.5kbps air bitrate, 50khz frequency deviation. If someone has better results with other settings please let me know.

They are powerful but will need more current to work, 130mA in transmit mode (for a short few milliseconds while the packet is modulated/transmitted), and the same 16mA in receive mode. So far the Moteinos in their current configuration seem to handle the high current spikes just fine.

HopeRF has suggested that 868Mhz units can be replaced with 915Mhz units that are loaded with 868Mhz settings. I have verified this myself with range tests and I don’t see any significant difference when using 915Mhz units at 868Mhz. Hence if you need 868Mhz units please get 915Mhz units and initialize them with settings for 868Mhz.

Wireless programming Moteino R3

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It works!

The last few weeks I have spent a lot of time tweaking the RFM69 library and trying to get the wireless programming to work. I believe the RFM69 library is now more stable and ready for some prime time and also the wireless programming is working nicely for Moteino R3. If you think about it, being able to reprogram a mote that is 200m away, or somewhere in a tree, underground, in your attic, or on the bottom of your pool, is a pretty cool thing.

I reorganized the Github repository a little, moved some files and now the classes for wireless programming are in their own repository to avoid conflicts with the SPIFlash lib:

https://github.com/LowPowerLab/WirelessProgramming

If you have a Moteino R3 (or R2) with the onboard FLASH chip, you are ready to try programming it wirelessly, go ahead, it’s pretty neat.

The examples for Moteino R2 and R3 are in the directories for their libraries: RFM12B and RFM69.

More great stuff is coming, I got a lot of ideas for Moteino R3, I am thinking of migrating my home wireless sensor network to R3 and implementing a lot more home automation on these.

RFM69 library and Moteino R3

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This is the library that I’ve been working on for the new RFM69 modules from HopeRF. I consider this an initial beta release and it surely is a work in progress, it may contain bugs, but the provided Gateway and Node examples should work out of the box and illustrate basic usage. Please let me know if you find issues. The syntax is a little similar to that of the RFM12B library, but I went with some new conventions on naming and overall structure to improve readability and overall code quality.

This is a video introduction to Moteino R3:

This is a new product and the library needs more testing and performance tuning. The library currently is tuned for fixed 433/868/915 Mhz frequencies, and a 50khz bitrate, 50khz frequency deviation. I am hoping others will contribute and test the library to find the best combination of these settings and power level vs range vs frequency vs bitrate, etc.

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