Author Topic: RFM69HW Uno initialization hangup  (Read 1383 times)


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RFM69HW Uno initialization hangup
« on: March 12, 2015, 04:00:01 PM »
Hello all! So i'm getting pretty frustrated. I am trying to get my chips working with absolutely ZERO luck so far. I have searched the forums and the web and have yet to come up with a good answer. My first question is this (as it might save a lot of reading for everyone) there a status led (or any way to mount one so I can have a little more confidence my chip works?

If thats not it, the main problem I am having is that it is hanging on radio.initialize()
 I have made two separate breakouts for the chips and both are behaving in exactly the same way. I am connecting to a uno r3 (only have 5v arduinos). I have the arduino powered with a barrel plug and have a usb plugin for serial viewing. I have the following connections running through a step down configurations with 10k going to ground and 4.7k going to the following:

  • NSS: pin D10
  • MOSI: pin D11
  • SCK: pin D13

In addition MISO goes to pin D12 and DIO0 goes to pin D2

When i set the pins as output and set their voltage to high, jumpers from NSS MOSI & SCK all read 3.3 v (well a little higher).

I have 3.3v of regulated power (confirmed) going to the RFM69 and a common ground between the arduino and RFM 69.

I have attempted to comment out the initialization (though it wouldn't do much good in the grand scheme of things) and am able to get a couple of test lines out, but I'm starting to get pretty frustrated that I can't get ANYTHING. I feel like it's probably unlikely that I have 2 bum chips, but I suppose its possible. Then again, I could have just made a stupid mistake as well. Anyway, here are a few pictures of my setup, if it helps. I'm using the standard gateway code in the examples library. I'd be happy to upload my code if that would help the process. I didn't because I know everyone helping here is familiar with the library and example, neither of which I changed much. The only changes I have made is to comment/uncomment the appropriate frequency as well as uncommenting the segment that defines the chip as high power.
« Last Edit: March 12, 2015, 04:03:00 PM by kennedyl »


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Re: RFM69HW Uno initialization hangup
« Reply #1 on: March 12, 2015, 06:46:57 PM »
Hi kennedyl,
From what you're saying and showing it looks like you're doing everything right, at least I can't spot anything wrong.
You're saying it hangs in init(), how do you know that's the case?
I recently patched the library to avoid any such hangs that were possible in some rare instances, so I would not expect initialize to hang.
You will have to add your own debugging statements in the library and trace down where your code freezes.
Otherwise I am not sure how to help. I am more concerned about the library than an ArduinoUNO+RFM69 setup since that is a frequent topic where a lot of people are having issues and trying to help everyone is very time consuming. So in light of that ... i hate to give this answer, but if your time is worth anything, I would just get a Moteino or another tested product that guarantees you have a working board with a working radio.


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Re: RFM69HW Uno initialization hangup
« Reply #2 on: March 13, 2015, 08:45:04 PM »

Those flying leads are likely to be too long for successful SPI transactions.  Either shorten those paths dramatically or slow the SPI clock speed down.


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Re: RFM69HW Uno initialization hangup
« Reply #3 on: April 19, 2015, 01:05:20 AM »
check D0 pin