In the “ESP8266 Thing Development Board Hookup Guide” is says the ADC pin can only measure up to 1V. I need to measure an analog input from 0V to 3.3V.
Do any of the other measure analog input?
Why does it say all pins can take 3.3V but this one is only 1V?
Can I hook up a Nextion touch display to the TX anr RX pins?
The technical info for the ESP8266 suggests the lone ADC input is rated at 0-3.3V. You may want to contact SFE directly as to why they recommend +1V max.
Scratch that - their latest datasheet says "*The input voltage range is 0 to 1.0V when TOUT is connected to external circuit*". So you are looking to use a voltage divider prior to hitting the ADC input.