<![CDATA[[BUG] analogRead(35) beeps]]>That's uncommon.
Try this out:

#include <M5Stack.h>

void setup() {
M5.begin();
}

void loop() {
float v = analogRead(35);
}

]]>https://community.m5stack.com/topic/159/bug-analogread-35-beepsRSS for NodeWed, 29 Apr 2026 01:32:26 GMTThu, 05 Apr 2018 21:17:44 GMT60<![CDATA[Reply to [BUG] analogRead(35) beeps on Fri, 06 Apr 2018 17:36:27 GMT]]>@dda So it is the "shut up"function ! ha ha

]]>https://community.m5stack.com/post/751https://community.m5stack.com/post/751Fri, 06 Apr 2018 17:36:27 GMT<![CDATA[Reply to [BUG] analogRead(35) beeps on Fri, 06 Apr 2018 03:27:44 GMT]]>@daslolo #define SPEAKER_PIN 25 --> src/utility/Config.h

void SPEAKER::mute() {
  ledcWriteTone(TONE_PIN_CHANNEL, 0);
  digitalWrite(SPEAKER_PIN, 0);
}

--> src/utility/Speaker.cpp

Basically, it's telling the M5 speaker to shut up.

]]>https://community.m5stack.com/post/741https://community.m5stack.com/post/741Fri, 06 Apr 2018 03:27:44 GMT<![CDATA[Reply to [BUG] analogRead(35) beeps on Fri, 06 Apr 2018 00:40:29 GMT]]>@calin thank you, this did it.
Could you explain what was happening and why dacWrite(25,0) is working?

]]>https://community.m5stack.com/post/738https://community.m5stack.com/post/738Fri, 06 Apr 2018 00:40:29 GMT<![CDATA[Reply to [BUG] analogRead(35) beeps on Thu, 05 Apr 2018 23:22:17 GMT]]>add dacWrite(25,0); after M5.begin(); and the noise will be gone.

]]>https://community.m5stack.com/post/736https://community.m5stack.com/post/736Thu, 05 Apr 2018 23:22:17 GMT<![CDATA[Reply to [BUG] analogRead(35) beeps on Fri, 06 Apr 2018 00:47:19 GMT]]>So the DSOs have voltage dividers not voltage regulators?
Good to know about noise causing spikes like that. I read that 3.3V on the EPS input is the maximum and more could damage the chip, ouch. How do I know if I damaged my esp32?

@calin 在 M5Stack 2 Channel Oscilloscope 中说：

Some basic filters and voltage dividers at the input pin, can solve that problem.

I'm familiar with voltage divider but what are examples of basic filters?

]]>https://community.m5stack.com/post/731https://community.m5stack.com/post/731Fri, 06 Apr 2018 00:47:19 GMT