I have “ESP IS NOT RESPONDING” in blynk esp8266 shield code
Tx–》2
RX–》3
GND–》GND
Vcc,ch-pd—》3.3v
In upload gpio0—》GND
Common problem, many reasons… One primary reason is that you NEED separate 3.3v power for the ESP… do NOT power it from the Arduino’s 3.3v pin (but you do need to share the ground connections between both arduino and ESP).
Read this for more info
http://help.blynk.cc/how-to-connect-different-hardware-with-blynk/arduino/esp8266-with-at-firmware
What is the difference between external and arduino
Also, you do NOT need this as it is for programming the ESP in standalone mode (AKA, NO Arduino)
Current capacity… the Arduino’s 3.3v regulator is NOT designed to supply the current to power an ESP, so you need an external 3.3v power source rated MIN 800mA - 1A
Click on the green link and read the document!
Ok thank you
It is also a (overly debatable) issue, but since the Arduino’s TX port is 5v and the ESP’s RX port is only supposed to receive 3.3v, you need the resistor based voltage divider as mentioned in the document.
Yes, it may survive without it, or it may not… but why take the chance 
The ESP’s TX to Arduino’s RX is just fine as is.
The esp-13 shield make it easy ???
I haven’t used the ESP-13, just the ESP-01 (as a shield)… but they are the same in basic principle as far as using it as a shield is concerned.
However if your ESP-13 is already mounted on an development board then it may have USB for programming and more GPIO pins available and thus better suited for standalone use (in which you program and use the ESP itself, not the Arduino thru the ESP).
Here is the link for that use case
http://help.blynk.cc/how-to-connect-different-hardware-with-blynk/arduino/esp8266-standalone
If you are shopping for a optional MCU, look at the NodeMCU or Wemos D1 Mini as they are easy to program (using the same Arduino IDE and programming language) and connect to breadboards for sensor hookups etc
https://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20171130000933&SearchText=NodeMCU
My project need more pins ;i use it with mega or uno
(ESP-01 in the upper left)
I don’t have 3.3 regulator can use 3.4v
Again thats debatable, but I personally don’t see the 0.1v being a deal breaker… at least until you can get a proper sized one.
esp can work safely up to 3.6v, so yes, 3.4v is fine. just make sure can supply enough current and use filtering caps on the regulator.
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I try is link same thing but esp8266 blue light turned on and i try software serial and hardware
I have two ESP-01… the one on the MEGA has Red LED for power and Blue LED for serial communication, the 2nd ESP-01 (the newer one) just has the Blue LED for serial transmission only when programming (also linked with GPIO2). They removed the power LED to save power with battery applications.
With the MEGA use the Hardware Serial1 pins (TX1-18 RX1-19) and 115200 BAUD (make sure your ESP-01 is still programmed for that BAUD rate).
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It’s on 9600 baud what is the difference
It is slower… SoftwareSerial can only handle 9600 (thus used for the UNO) but the MEGA’s Hardware Serial can go faster.
But since your ESP is set to 9600, you need to set the MEGA’s BAUD rate to 9600 as well then.
Same thing “esp not responding”
And i can’t write At command in putty app