ESP32 Forum

Posted: **Wed Jun 22, 2022 5:13 am**

in the official docs, it shows:

analogSetWidth¶
This function is used to set the hardware sample bits and read resolution. Default is 12bit (0 - 4095). Range is 9 - 12.

anyhow, it seems to me that the range of the output doesn't change, no matter what the parameter is, 9,10,11,12. why?
anything wrong to my code?

Code: [Select all] [Expand/Collapse]

#include <Arduino.h>
 
void setup() {
  Serial.begin(9600);
  pinMode(A3, INPUT);
  analogSetWidth(9);
}
 
void loop() {
  Serial.println(analogRead(A3));
}

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Posted: **Wed Jun 22, 2022 7:37 am**

I think setWidth is being deprecated. In v2.0.3, there is analogReadResolution(uint8_t bits). Can you try that and see if it works?

Posted: **Wed Jun 22, 2022 7:56 am**

many thanks!

I tried, just like what you said. it seems that you are right.

in fact, this CMD just misfunctions, which means that the range is incorrect, but it does change the sampling pattern. for example, one bit of every 8 bits is sampled, for the parameter (9). And, the sample will change correspondingly when the parameter is changed from 9 to another one, e.g. 10,11, or 12.

when the parameter is 12, you will see all the bits, the output will be 0,1,2,3,4,5,...,4093,4094,4095.

May I know from when it was deprecated?

ESP32 Forum

why the range of the output is from 0 - 4088 for analogSetWidth(9)?

why the range of the output is from 0 - 4088 for analogSetWidth(9)?

Re: why the range of the output is from 0 - 4088 for analogSetWidth(9)?

Re: why the range of the output is from 0 - 4088 for analogSetWidth(9)?