Transceivers

Here is a quick side by side comparison of different HopeRF radio transceivers. There are different aspects of compatibility between them which we discuss below.

For the transceivers to work properly with the RFM69 library, you must always check the radio settings in your sketch. Particularly the RFM69HW and RFM69HCW radios require invoking radio.setHighPower() after radio.init() (usually controlled by the #define IS_RFM69HW_HCW directive), see how this pattern is implemented in the library examples. For RFM69W & RFM69CW you should *not* call radio.setHighPower() – ie comment out the #define IS_RFM69HW_HCW line. Doing this incorrectly will result in no wireless range and can even damage your transceiver!

All Moteinos now accept these types of transceivers:

What is the difference between W/CW/HW?

The W/CW/HW are different configurations of the same Semtech SX1231h transceiver chip (custom packaging by HopeRF). They come in different transmission power and frequency variants. For instance the W and CW are 13dBm power output. The HW and HCW are 20dBm power output.

All RFM69 radios can communicate with each other regardless of their configuration/layout (as long as the above settings are correctly set) when their network ID and encryption (optional) keys match. Their node IDs should be unique, the RFM69 library supports up to 255 nodes per network. The broadcast address is 255, sending a message to that node ID=255 will make all listening nodes receive that message.

Pin compatibility

The W and HW are pin compatible. The HCW are only pin compatible with the RFM95/96 LoRa radios. The CW radios are pin compatible with the older RFM12B.

Code/settings compatibility

The W and CW are equivalent in coding and settings usage, and same is true for the HW and HCW. In fact, the only setting difference between W/CW and HW/HCW is the very important #define IS_RFM69HW_HCW directive discussed above.

Frequency markings

Since it’s not easy to distinguish between the same radio of different frequencies (except marked on the bottom by HopeRF), LowPowerLab has its own marking convention for the transceivers to quickly identify frequency once they are soldered to Moteinos. The 433mhz radios are marked with a gold dot. The 868/915mhz are marked with a silver dot. Other vendors also mark their HopeRF radios but have different colors.

RFM69 and RFM95/96 LoRa compatibility

RFM95 and RFM96 are *not* compatible with RFM69 and require a 3rd party library, see the LoRa page for details. However RFM6 (HCW only) and RFM95/96 LoRa radios are pin compatible, enabling them to share the same mounting pads.

Chip marking confusion between RFM95 and RFM96

RFM95 and RFM96 can be confused because they both have a chip marked with “RF96“. They are in fact different, as can be noticed in the photo above. Although the chip is the same, the components are mounted differently, reflecting their different frequency operation. The markings on the back of the module also makes this distinction.

What about RFM12B?

RFM12B can be used on Moteino/MoteinoUSB/MoteinoMEGA but this radio is not supported for new development and older code/library is only kept for reference.