Pro Micro and RFM69

Projects Programming
1

I made a project using 32u4 and RFM69 to send data from my heating furnace to my living room (temp, etc). As RFM69 works at 3.3V, I made everything on that voltage level, 32u4 too. This part works like a charm. I can upload sketches and it works. So, 32u4 has its 8MHz crystal and works at 3.3V.

RFM69, however, works... sort of.
Connecting the RFM69 module with 32u4 is based on Adafruit Feather 32u4 Radio with RFM69HCW Module (Overview | Adafruit Feather 32u4 Radio with RFM69HCW Module | Adafruit Learning System)

I use Radiohead lib, examples->radiohead->feather->radiohead_rowdemo_rfm69rx/tx.
When I upload the TX on the first one, I can see it communicate with the module.

Feather RFM69 TX Test!

RFM69 radio init OK!
RFM69 radio @868 MHz
Sending Hello World #0
No reply, is another RFM69 listening?
Sending Hello World #1
No reply, is another RFM69 listening?

When I upload RX on the other one, I can see it communicate with the module, but there is no data.

32u4temp
32u4temp1170×828 58.8 KB

Both devices are the same.

Now, I know there are power issues. I set transmit power on 15. There is power from the PC on USB and the 18650 battery on both of them. The range between them is a few meters.

What should I check, how to troubleshoot this?
If needed, I can post an actual image of the project.

2

I've used RFM69 modules (433mHz) for a while. I didn't get much joy with the Radiohead library or the MySensors library. What worked flawlessly for me was the LowPower lab RFM69 library. The examples were easy to follow too.

3

Thank you for the link. Monteino is looking great.

However, one must read the damn documentation. I forgot to mention, I use RFM69CW. In examples, by default, everything is set for RFM69HCW. Wich is not the same.
I commented out the setTxPower() on both sketches and everything works like charm.

Read the damn documentation.

Read the damn documentation.

Read the damn documentation.

Read the damn documentation.

Read the damn documentation.

Oh, well...

4

The first thing to check in this sort of setup is whether the transmitter is actually transmitting a packet at the correct frequency.

At a minimum an el-cheapo SDR is almost essential for checking for transmissions, or a UHF handheld if the frequency were 434Mhz.

5

Something like this?

6

Aye, like that, you might find them cheaper with a bit of searching.

The ones with decent antenna socket on the end, like the one in the link, are easy to attach antennas to.

7

I get the dongle, but to be honest, not sure where to start.

Can you give me some clues, links, etc?
What software, for a basic start?

8

This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.