Analog pin on node mcu 1.0 (esp 12F) in range 0-3.5V??
Posted: Sat Jun 24, 2017 4:12 amHi,
I read on the esp 12F datasheet that the ADC pin reads between 0 - 1V. Also, anything I've found online referring to the nodemcu or the esp states that it has a 0-1V range and a 10 bit resolution. However, I'm having some curious problems....
I recently bought the module and I've been flashing it with the arduino IDE. Here is my test code:
The problem: For some reason, I'm struggling to get a reading of 1024. I've unplugged everything and then connected the A0 pin to the GND and I get a reading of about 8. I'll say that's okay. However, when I connect 3.3V GND to A0, I get around 996. When I connected to 5V I get 1024. I then put a potentiometer between 5V and A0 and changed the voltage until I found the approximate voltage at which the analog reading changes from 1023 to 1024 and I found it to be ~ 3.5V. It seems that the analog pin range is between 0-3.5V rather than 0-1V. So, what's going on and how do I change it?
P.S. My exact purchase is this: https://www.aliexpress.com/item/5pcs-Wi ... 0.0.WA7IpN
Thanks in advance for any help!
I read on the esp 12F datasheet that the ADC pin reads between 0 - 1V. Also, anything I've found online referring to the nodemcu or the esp states that it has a 0-1V range and a 10 bit resolution. However, I'm having some curious problems....
I recently bought the module and I've been flashing it with the arduino IDE. Here is my test code:
Code: Select all
const byte ADC = A0;
void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
}
void loop() {
// put your main code here, to run repeatedly:
int reading = analogRead(ADC);
Serial.println(reading);
delay(3000);
}
The problem: For some reason, I'm struggling to get a reading of 1024. I've unplugged everything and then connected the A0 pin to the GND and I get a reading of about 8. I'll say that's okay. However, when I connect 3.3V GND to A0, I get around 996. When I connected to 5V I get 1024. I then put a potentiometer between 5V and A0 and changed the voltage until I found the approximate voltage at which the analog reading changes from 1023 to 1024 and I found it to be ~ 3.5V. It seems that the analog pin range is between 0-3.5V rather than 0-1V. So, what's going on and how do I change it?
P.S. My exact purchase is this: https://www.aliexpress.com/item/5pcs-Wi ... 0.0.WA7IpN
Thanks in advance for any help!