Reading from analog sensors via ADC MCP3008

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Hi,
I want write a plugin that reads analog data via an analog to digital converter, the MCP3008.
I followed this tutorial and managed to receive converted analog values from simple soil humidity sensors. While those do have a digital and analog output pin, the digital output returns just 0 or 1 and nothing between - truely digital!
Attached to the ADC I got high resolution values between 0 and 1024, which I can read via the tutorial’s Python script.

How can I make a plugin run the script and display the output? Is there something similar already?

Thanks for any hints,
nkoder

@nkoder Hi, One possibility is device ShellSensor. from pimatic-shell-execute plugin.

Thanks, I’ll try that!

If you switch to an PCF8591 expander which provides 4 analog inputs you can use pimatic-johnny-five. Another possibility is to use an Arduino Mini which also has an 10-bit A/D converter intergrated. This can also be used with pimatic-johnny-five

http://johnny-five.io/examples/expander-PCF8591/
https://www.arduino.cc/en/Tutorial/AnalogInput

Thanks,

the shell-execute plugin works great!
this is the config for my sensors:
{
“id”: “soil-hum-1”,
“name”: “Soil Humidity 1”,
“class”: “ShellSensor”,
“attributeName”: “soil-humidity-1”,
“attributeType”: “number”,
“attributeUnit”: “%”,
“command”: “python /home/pi/readFromADC.py 0”,
“interval”: 500
},
{
“id”: “soil-hum-2”,
“name”: “Soil Humidity 2”,
“class”: “ShellSensor”,
“attributeName”: “soil-humidity-2”,
“attributeType”: “number”,
“attributeUnit”: “%”,
“command”: “python /home/pi/readFromADC.py 1”,
“interval”: 500
}