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Temp sensors considerations

gohan Mod last edited by
I have been running 3 temp sensors on the same board for testing: BME280, SHT31 and MCP9808.

This is the graph of the latest data.
BME280 is running with a -0.7°C offset because I wanted to compare it side to side with the MVP9808 as it was constantly reporting 0.7°C more then the other.
SHT31 is constantly reporting 0.5/0.6°C more than MCP9808.
Accuracy of sensors according to datasheet is:
- BME280 0.5°C at 25°C or 1°C between 0-65°C
- SHT31 0.2°C
- MCP9808 0.25°C typical 0.5°C maximum
Could I assume the real correct temperature is like 0.2°C below the reported temp of the SHT31?
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@TheoL Not only did I put in delays, too, but I put in delays that were based upon the ID (which was stored in NVRAM)! This helped. caveat: This is probably not accurate be helps to explain the challenges with a large network. My initial experience with Arduino/nRF24 was using the libraries from TMRh20. Those libraries allowed a node to be a repeater, but only for 6 nodes. The primary node 0, master, only allowed 6 nodes to connect to it. The nodes connected to it also allowed 6 nodes. Subsequent nodes had to go through one of these repeating nodes. But the depth was only 4 deep. The master assigned node IDs if the node didn't already have one; similar to a MAC address. The master also kept track of the addresses (ARP table?). Addresses were 4 octets (base in the form of D/C/B/A. A node connected directly to the master had an address of 0/0/0/a (where 0/0/0/0 was reserved for the master). A node connected through another node had an address of 0/0/b/a, and so forth. But what happens is that a parent node has to mange the data from all its child nodes and their child nodes and their child nodes. Thus a node would get so bogged down dealing with this traffic that it din't do its sensor task very well. It is my belief that MySensors either uses TMRh20's libraries or has developed some aspects based on his initial work. I see that that TMRh20 has a version 2 and I have not experimented with it. I did find that MySensors worked better than version 1. Thus, my curiosity. I am also duly impressed at the magnitude of hardware. Currently a nano like device from Aliexperss is US$2-3, nRF24 ~ US$1, power supply ~ US$1.50, power cord ?, case?, sensors!? While the hardware cost is daunting, even with a PCB it's a lot of work building those up. So, yeah, I'm impressed! -OSD
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hey @dirkc, maybe you can trigger your interrupt to rising and falling edge and use millis() to see how long the press was?
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@mimaret It was a pleasure. Thank you for your feedback!
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LiFePO4 batteries are a great choice because they have a long life cycle and are much safer than other lithium-based batteries. However, you need a solar charge controller that’s compatible with LiFePO4 to prevent overcharging and maintain efficiency. A good MPPT controller can significantly boost energy harvest from your panels. Also, ensure your solar panel output matches your power needs. If you're in solar ireland, you might find some local companies that offer tailored solutions for maximizing solar efficiency in lower light conditions.

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