I was experimenting with a Arduino SigFox device MKRFox1200 and discovered that i also need some 4-20mA input connection.
So in stead of trying to attach some inport opamps to the MKRFOX1200, I wondered if i can connect some sigfox device to your Industruino IND.I/O D21G. Maybe some Breakout board like https://yadom.eu/carte-breakout-sfm10r1.html ?
Yes we have an expansion port on the INDIO for communication modules such as Ethernet and GSM/GPRS. These 14-pins provide direct access to the MCU, including 2 hardware serials, so you can easily wire them to a serial Sigfox module as the one in your link. This is similar to hooking up an ESP8266 serial wifi module (also using AT commands) as documented here https://industruino.com/blog/our-news-1/post/adding-wifi-to-the-industruino-esp8266-16
Pinout is here https://github.com/Industruino/libraries#idc-pinout
You will need to add a voltage regulator if you need 3V3.
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