M5Stack: M5.BtnA.wasPressed() conflicts with WiFi

[evanevery]

I reported this in the M5Stack community forum and also the M5Stack Github. Someone else also found this problem and reported that if the IDF was rolled back it went away. (http://forum.m5stack.com/topic/174/m5-btna-waspressed-conflicts-with-wifi) So it looks like this is an issue with the current IDF:

It appears that M5.BtnA.wasPressed() will not work properly if the M5Stack is currently connected via WiFi. It appears that BtnA can not be reliably used if the device is connected via WiFi. The pin appears to become unstable or maybe is being used for some other WiFi related function.

Leave code below as is to see unstable BtnA. Comment out just the three WiFi connect lines to see BtnA working as expected:

----- Code Below ---------------

#include <M5Stack.h>
#include <WiFi.h>

void setup(){
M5.begin();

 // Comment out the next three lines for Button A to work properly
 WiFi.begin("SSID", "PWD");
 while (WiFi.status() != WL_CONNECTED) {
 }

 M5.Lcd.println("Ready!");

}

void loop() {

 if(M5.BtnA.wasPressed()) M5.Lcd.println("Button A");

 M5.update();

}

[reaper7]

additional information:
m5stack button A is connected to GPIO39

m5stack/M5Stack#52

[evanevery]

OK... So why is that important?

[reaper7]

it may be important...
not everyone knows what is BtnA

[drschlaumeier]

I have same problem.
Anyone has already solution?

[evanevery]

Not so far!

If you use M5Stack WiFi, then you can not use Button A. Only TWO buttons are usable!

[drschlaumeier]

Hmm, seems to be in the espressif core and not the libs. There is a similar issue documented.

espressif/esp-idf#1857

Track down the root cause is difficult...

[evanevery]

All I can do is lay the problem on the altar and hope someone fixes it...

We only have three buttons and to lose one of them just cause WiFi is being used seems to be a pretty big loss of functionality...

[negativekelvin]

espressif/esp-idf#1806

[drschlaumeier]

Thanks for the hint. I understood RTC causes problems and/or ADC1 needs to be disabled. Correct?

[drschlaumeier]

Hey, took me a while with Try&Error to disable ADC, ISR, DAC etc. until I recognized thats only a shit timing issue.
A smal delay(10) helps and btnA is reading normal !

void loop() {
  delay(10);
  if(M5.BtnA.wasPressed()) M5.Lcd.println("Button A");
  M5.update();
}

[evanevery]

Did you try this with WiFi enabled?

[drschlaumeier]

sure

[evanevery]

Yup... Just tested it with my very simple test code and it seemed to mitigate the issue! Thanks!

Now I need to test it in my real world sketch to see if it helps....

[evanevery]

Seems to mitigate the issue in my "real world" sketch as well.

Its a simple work-around, but it costs 10ms. Hopefully it will help someone find the root cause and actually fix it!

Nice! Thanks!