Project of Breadboard holding RFM95

(Ccadic) #1

I made it available on GITHUB :
I can connect an I2C Oled Display and an EUI ID number chip (working as a I2C component to read the value)

SMA Edge antenna can be soldered onto the board.

Overview of custom shields and breakout board designs
(Ccadic) #2

I finished the mending

(Ccadic) #3

(Ccadic) #4

First tests are positive. Was able to create and connnect the first prototype as a node to my ic880a gateway

You can find the code there : (with the gerber files also)

I still have a few PCB there:

Tonight I will solder the EUI I2C identification chip and OLED.

If I have time I will also make a nodemcu PCB and add some option such as LED blinking when data is sent or received. Option to save energy and GPIO points available on board's holes.

(Ccadic) #5
  • Go to and add the ZIP library to your Arduino IDE
  • Connect your NODE MCU as this
  • D1 (GPIO5) - DIO0 (SX1275/RFM95)
  • D2 (GPIO4) - DIO1
  • D5 (GPIO14) - SCK
  • D6 (GPIO12) - MISO
  • D7 (GPIO13) - MOSI
  • DO (GPIO16) - NSS
  • GND - GND
  • 3.3v - VCC


Very nice! thanks for sharing!

(Ccadic) #7

My pleasure
Now making the tutorial based on a nodeMCU and then a NanoV3
I have issues with the NodeMcu, not enough Gpio available to run the Oled Screen and RFM95 simultaneously

(Ccadic) #8

I manage to wire the item on an Arduino NanoV3 (I updated GITHUB). The arduino has more GPIO pins than the ESP8266 and I feel it is much better for building a true node.
The NanoV3 memory is to small for managing the RFM95 AND OLED screen at the same time. 16 kb is not enough (adafruit library is probably the reason). I have to wait until I get an arduino clone with more memory. (0.3 kb are missing)
There is also a part of the code to add to read the Identification chip.
All of these functions work separately with my prototype, but cannot pack them together because of this small 16k meomry barrier


if you just miss a few GPIO on your Node MCU, there is a possibility to OR the RFM95 DIO0-DIO2 Pins, check and the associated schematic.

There is also a schematic for Node MCU where RFM95 and OLED IC2 are used in parallel: .

(Ccadic) #10

Tnx much for the advices. (I'm beginning.. lots of things to learn at the same time )
I've ordered 2 boards from the links you gave me. It'll be interesting to learn from exemple
I'll try and make correction tomorow night


You can also consider to use the LMIC port from Charled Hallard which does not need any DIO or reset at all. He submitted a pull request to the de-facto TTN LMIC stack from Matthijs Kooijman. I understand the Maarten Westenberg (things4u) LMIC port has some nice optimizitions with regard to code size. Didn't compare this yet with the above ones because they have suited all my needs untill now.

(Ccadic) #12

I'll have a look. Would be great if I can shorten the code :slight_smile:

(Martinlocher) #13

This is awesome. Makes us deliver scaleable nodes with low power and low money :slight_smile:


Is there a pcb shield available where i can place a arduino nano v3 and rfm95 to combine?


Hi again, after some browsing on the internet build, i found nothing. i make a new pcb with Fritzing for a nano and RFM95, see picture arduino%20nano_nrf95.

Ordered some prototypes by Aisler. When the prototype works, a copy of the project will be found on github.

(M2mlorawan) #16

You can find this PCB kicad file on the net. It is well tested and works well.



A arduino pro mini is not a nano :slight_smile:

(Matias S Timi) #18

Hi . Do you have the link for download the PCB files? I can’t find them. Thank’s