and other man's report https://www.facebook.com/photo.php?fbid ... 912&type=3
GPIO0 of ESP8266EX can output the clock frequency of the external cystal(e.g. 26Mhz or 40MHz) by default.
Please check it by measuring the frequency of this bizarre wave.
Any more questions, please let us know.
Frequency is 27.5MHz
https://www.facebook.com/photo.php?fbid ... =3&theater
> GPIO0 of ESP8266EX can output the clock frequency of the external cystal
Why is the voltage from -1V to 5V over this GPIO0?
This voltage from -1V to 5V gives damege to my circuit.
Wave at download time is https://www.facebook.com/computerartisa ... 369391869/
My friend observed that wave https://www.facebook.com/photo.php?fbid ... 912&type=3 .
Yellow wave is GPIO0's wave.
magenta wave is RESET's wave.
Yellow wave's behavior was as follows
(2)from -0.5V to 4.0V 26MHz wave.
(4)from -0.5V to 4.0V 26MHz wave.
I think that bootloader has bug.
Not the end of the world but I do think it is a bug because GPIO0 is also used as input during boot. Unfortunately it's baked in the boot ROM so we'll have to wait for the ESP32 to fix this
If the voltage overshoot causes problems you could add a resistor and a zener diode to clip it to 3.5 or so volts?
Who is online
Users browsing this forum: No registered users and 1 guest
Newbies Start Here
Are you new to ESP8266?
Unsure what to do?
Dunno where to start?
Start right here!
We also have a RTOS version and a MESH version too!
Complete listing of the official ESP8266 related documentation release by ESPRESSIF!
Must read here!