CubeCell Programming, Additional Tips and Information

#1

Heltec Cube Cell Product is a great product using ASR65001/2 with SX1262.

I have now been using the product for a few weeks. I have found a number of issues and produced a guide for the people on how to use it and some of the pitfalls to ensure you can get an operational LoRaWAN node. I use the product on TTN so I need to have working LoRaWAN Scripts and not just Sensor code onthe CubeCell

This is not a Vendor guide and I recommend that you the Heltec ones on this site .

This document is located in my GitHub https://github.com/Securethingsuk/Heltec_CubeCell and I have added some “Working” sketches for LoRaWAN_BME280.

I would also like to comment regarding sleep current. The best I have obtained is around 20 ÎĽA not the initial 3.5 ÎĽA which as Heltec have stated only occurs in some special conditions on a 3.3v VDD connection in deep sleep mode.

The Board manager need to have a file updated, if you want to use the BMP/BME range of sensors as define by Raystream ( I waiting for a 0.0.4 Board manager .There are other issues such as: -Vext power line settle time, -TX output power, -Antennas, -AT Commands, -Key programming.

I will update as needed as time goes on and I am happy to receive other views and comments and if anyone gets LoRaWAN Solution with other sensors working that are not In Heltec Github, then happy to have them uploaded to my site .

I hope this helps those that have CubeCell Products or considering buying one.

Simon Collins

4 Likes
#2

Thanks Simon for your most useful insights and feedback.

I’m still discovering it but CubeCell looks like a very promising product and our community needs to be able to help making it even better.

Cheers.

#3

would be great if there would be a source code version of the CubeCellLib.a
i would like to add some more AT commands.

The HDC1080, CCS811 and BMP280 Sensors combined in the CJMCU-8128 Module are working just fine for now more than a week in my test capsule running on battery.

I am working on the BME680 right now and should habe a running version at the end of the week.

all my work is in my GitHub repository at: https://github.com/raystream/ASR650x-Arduino

If you need adapterboards for using the bme680 or MJMCU-8128 breakouts directly in your capsule or a complete ready to use sensor you can get that on https://www.lora8.eu

#4

just downloaded the latest version from the HelTec GitHub Repository and found some errors.
most typos but repo cant compile with them.
I fixed all bugs i have found and a functional version is now found in my GitHub Repo:

#5

Nice work, thanks. FYI You don’t need to be editing commissioning.h, you can just extern the variables and memcpy over those keys. Works well.

#6

Thank you!

In the Programm i found:
float temperature = (bme280.getTemperature()); //In Deg C
float pressure = (bme280.getPressure()/100); //Presssure in HPa
float humidity = (bme280.getHumidity()); // in %
float altitude = (bme280.calcAltitude(pressure*100));

puc = (unsigned char *)(&temperature);
AppDataSize = 18;//AppDataSize max value is 64
AppData[0] = puc[0];
AppData[1] = puc[1];
AppData[2] = puc[2];
AppData[3] = puc[3];

I think, the common medium of air is a limited commodity. Airtime should therefore be used as short as possible. So, don’t ask yourself how easy you can possibly send but rather ask how few Bytes could do the job. The temperature, for example, can be transmitted as 16 bit integers or one byte. Decimal points can be represented by multiplication, but the sensor has an accuracy of one °C.

#7

Hi I agree it can be cut down and send less data and yes it does have an absolute accuracy of +/- 1Deg C though at the time, I was looking for incremental change / I will udate in the future as it save power and air time.

Simon