Hi I'm new to raspberry Pi and node-RED and I need to connect 8 Pt 100 sensors to Raspberry Pi using 8 MAX 31865 chips (with SPI protocol) and MAX 31865 node. Does this node let you use 8 GPIO pins to select one chip at a time instead of the default CE0 and CE1 ??. These default SPI select pins are limited to tow devices only.
Welcome to the forum!
If you look at the node's readme it says:
If you would like to connect multiple MAX31865's to a single Raspberry Pi, have them share the MOSI, MISO and SCLK pins. Then assign the first board the CE0 pin and the second board the CE1 pin.
More details on the Raspberry Pi pinout: SPI at Raspberry Pi GPIO Pinout
You might be able to find a way to use more, but I would venture that the way the node is written, two is all it supports.
You could open an issue on the authors GitHub page and see what will come of that. Good Luck.
One other thing you coyld do is use an arduino (with WiFi) to read a sensor (or two) and then send the results to NR onthe Pi using MQTT.
Thank you zenofmud for your response, I will post on the authors git page, but I wanted to ask if it is possible to use the second SPI on raspberry Pi (SPI1) to read two other chips (max31865) with node-red.
If I understood correctly there is a way to activate SPI1 on Rapberry Pi with 40 header, but I don't know if they will work together or if the node can be configured to read from SPI1.
I dont have any of the boards yet so i can't test them.
I think this is one of those things where you're going to have to test it and see if you can get it to work.
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