Hi all, I'm new to using arduinos, so just hoping your far more experienced people might be able to lead me down the right path.
I am trying to make a a device which will monitor temperature, and then send that information wirelessly to be viewed on an LCD screen ( or something similar).
I've been doing some digging in to what components I will need to do this, but I am a little hesitant on what to actually buy before I spend the money on it.
From what I can work out, I need:
a temperature measuring device
Two Arduino boards (one at the sending end, and one at the receiving end)
Two NRF2401 Transceiver modules
LCD output screen
Am I going down the correct route here? Is there any advice anyone can give? Don't want to buy the wrong components.
For measuring temperature I can recommend the DS18B20 digital temperature sensor. It is widely available (not just from Adafruit) and there are many tutorials on its use.
Uno boards are perhaps the easiest to work with. Nano is about the same, only smaller.
For a beginner I suggest a 16x2 or 20x4 with hd44780 controller character LCD with an I2C backpack. The hd44780 library makes interfacing to those LCDs easier. The library is available in the IDE library manager. You would use the hd44780I2C_exp class.
What is maximum distance between transceivers? Clear line of sight or obstructions like brick walls, cars, trees, metallic objects like refrigerators and other appliances,etc.?
The hd44780 library and an I2C LCD I also recommend as I have a pleasant experience of them, most likely because of @groundFungus.
Another questions is how to supply power to the 2 different arrangements. Are mains available in both places?
ArduinoBeginner74:
As for range, I chose the NRF24's because of the range, i need potentially around 100m in a built up area.
do you have WiFi in both places ? that would give you a more reliable transmission in a built up area.
ESP8266 are low cost and interface well with the DS18B20 or if you wanted to add humidity, the BME280
ArduinoBeginner74:
As for range, I chose the NRF24's because of the range, i need potentially around 100m in a built up area.
That seems a strange statement. 2.4GHz wireless is not good at penetrating obstacles.
With clear line of sight outdoors I have had over 100m range between two of the low power nRF24s (with the PCB antenna). From reading other experiences here I believe you would get a much greater line-of-sight range with a pair of the high power nRF24s (with the external antenna). However I don't recall anyone reporting his/her experiences of using the high power units with obstacles in the way.
For working in a built up area lower frequency wireless, such as the 434Mhz (have I got the number correct?) of the HC12 modules, would be better. However I have not used them myself as all my wireless projects have been short range.
Robin2:
That seems a strange statement. 2.4GHz wireless is not good at penetrating obstacles.
With clear line of sight outdoors I have had over 100m range between two of the low power nRF24s (with the PCB antenna). From reading other experiences here I believe you would get a much greater line-of-sight range with a pair of the high power nRF24s (with the external antenna). However I don't recall anyone reporting his/her experiences of using the high power units with obstacles in the way.
For working in a built up area lower frequency wireless, such as the 434Mhz (have I got the number correct?) of the HC12 modules, would be better. However I have not used them myself as all my wireless projects have been short range.
...R
I would concur, 100m in a 'built up area' is quite a chalenge for 2.4Ghz, the 'built up area' suggests that there might well be buildings in the way.
If there were specific reasons for sticking with 2.4Ghz, it is a Worldwide allocation and there are little or no duty cycle issues, then the SX1280 LoRa device might do the job, and even though I have had LOS of 89km out of them, I would still not be sure about 100m in a 'built up area'.
'high power' nRF24s may not be legal in a lot of places.
I would start by looking at 434Mhz ......................