LoRa Node with Wemos D1 Mini
-
Thank you Charles for creating the RFM95 Wemos shield. I have a gateway and 3 nodes working and really appreciate your articles and sharing your work. I am working on a very low power version of a node and need to put the Wemos into deepSleep.
I have discovered two very important problems and would like to know if anyone else has found them:
Using V1.2 of the PCB there is an error in the printing of the text. 'SEL' and 'RST' are the wrong way round! This is easily confirmed with a continuity check.
Second problem is deeper. The RFM95 module does not work with CS permanently held low because it seems to use the falling edge to set up a package exchange. It has 3 modes including a burst mode for reading or writing consecutive addresses and I think this may be why holding CS low does not work.
I solved this by using D1 for CS - I did not use pull ups on D1 & D2 because I am not using I2C. A short wire from the pad for the I2C chip to the pad marked RST (actually it is SEL) now allows the RFM95 to work correctly and I can use D0 to wake from deepSleep.
If anyone else is working on deepSleep this may be useful information and I would be very interested in your progress. I have more details if anyone would like to contact me.
Hello! It looks like you're interested in this conversation, but you don't have an account yet.
Getting fed up of having to scroll through the same posts each visit? When you register for an account, you'll always come back to exactly where you were before, and choose to be notified of new replies (either via email, or push notification). You'll also be able to save bookmarks and upvote posts to show your appreciation to other community members.
With your input, this post could be even better 💗
Register Login