Hi, I am working with a mangOH Yellow.
How does one connect an external sensor?
Thank you
- Oline
What sensor are you talking about?
Do you want to connect to iot expander slot?
Connecting to the IOT expansion card, would be really nice. But I am very new to this, so I have no idea how. I am working with a frequens / PWM water flow sensor.
What would I need to connect this?
What pins are needed on this sensor?
Uart? spi?
Thank you for your quick response. It is ADC. 
You can check the schematic of iot expansion card here: