I connected VCC to an Arduino's 3.3 volt and the GND to Arduino's GND. When I connect CH_PD tothe Arduino's 3.3 volt, it gets hot. While the red light is on, the blue light is on, too. On the serial side it sends some messages and I don't understand it. It also gets hot and that time I disconnected the CH_PD pin from the VCC. When I connect the power from two 1.5v AAA batteries, tt turns on and when I connect CH_PD to 3V of AAA batteries, the blue light turns on and after 0.5 seconds everything goes off.

My RX and TX connections are flipped, like this:

Arduino RX --> ESP TX

Arduino TX --> ESP RX

This is the message from the serial port:

ets Jan  8 2013,rst cause:1, boot mode:(3,6)

load 0x40100000, len 1856, r 
tail 0
chksum 0x63
load 0x3ffe8000, len 776, room 8 
tail 0
chksu201 ot
ms9de Sd:
rf cal sector: 249
rf[112] : 00
rf[113] : 00
rf[114] : 01

SDK ver: 1.5.4.c3oe 16:
hr2 11

All the tutorials on the internet say that CH_PD should be connected to 3.3V, and for the first time when I connected CH_PD to 3.3V that time I was able to send AT commands to it, with opposite of serial connections that I told you.

What can I do? Is my ESP dead? I really need this so please help me.

  • \$\begingroup\$ Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking. \$\endgroup\$
    – Community Bot
    Oct 29, 2021 at 8:07
  • \$\begingroup\$ I don't know about your precise problem, but as to the message you get on the serial connection, this is debug information, not garbage (serial connections are notorious for giving you actual garbage when the settings are wrong, so when you say garbage people will imagine something very different) \$\endgroup\$ Oct 29, 2021 at 8:19
  • 1
    \$\begingroup\$ Have a look here: stackoverflow.com/a/40422933 \$\endgroup\$ Oct 29, 2021 at 8:20

2 Answers 2


What you're getting on the serial connection is a debug message, not garbage.

It can give you clues as to what's wrong. For instance you can try to Google parts of the debug information to learn what it means.

In your case you have this "rst cause: 1". This site: http://iot-bits.com/esp8266/esp8266-reset-causes-rst-cause/ tells you that this message is normal just after applying power to the ESP, but if it happens randomly, it may indicate that the chip keeps resetting because the power supply is not able to supply enough current. This is one possible cause of overheating.

  • \$\begingroup\$ just boot mode is changing between 3,6 and 3,7 \$\endgroup\$ Oct 29, 2021 at 9:54

Aside from the restart problem, if you are talking about Arduino Uno, keep in mind that its 3.3V supply can source up to 150mA current (due to its LP2985 LDO ). It may or may not be a problem for startup, but when you try to connect to WiFi, ESP8266 will draw spikes of current that could damage your Arduino (and you won't be able to connect to network). I think using first an LDO (like LD1117, than can source up to 800mA) for 5V->3.3V conversion and then powering ESP8266 (both VCC and CH_PD) from that would be a better option overall.

  • \$\begingroup\$ I will try that \$\endgroup\$ Oct 29, 2021 at 9:36
  • \$\begingroup\$ Can I use this? amazon.com/HiLetgo-AMS1117-3-3V-Supply-Module-Charging/dp/… \$\endgroup\$ Oct 29, 2021 at 11:56
  • \$\begingroup\$ @AliAtaHashemi Well, I haven't used that, but it seems ok for your purpose. Look also at the link in DamienD comment, there is also mentioned the need for greater current source than built-in Arduino one, so the AMS1117 USB breakout you just sent should solve your problem \$\endgroup\$
    – p_a321
    Oct 29, 2021 at 12:18
  • \$\begingroup\$ Hey bro, I bought it and I'm using it, now it doesn't get hot. but I can't still use it. I don't know what's wrong. is there a way that I could know that is there any frameware on this device? \$\endgroup\$ Nov 10, 2021 at 11:13
  • \$\begingroup\$ My ESP8266 had preloaded firmware that accepted AT commands. You can try to send via UART the command AT+GMR. If it has the same preloaded firmware, it will return the firmware version. If i recall correctly, the default UART baudrate for ESP8266 is 9600. Keep in mind that you have a 3.3V ESP8266 and a 5V Arduino, which means that you need level shifting for proper UART comms between them ( the least you should do is a voltage divider in ESP8266 UART RX, else search for UART voltage level shifting ) \$\endgroup\$
    – p_a321
    Nov 11, 2021 at 9:35

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