ESP8266 Community Forum

Hi everyone,

I am a novice in ESP8266 and I try to flash NodeMCU using esptool.py. I have this convertor PL2303. I connected RXD to TX, TXD to RX using cd4050 to convert 5V to 3.3V on these pins. I connected GND, GPIO0 to GND and VCC, CH_PD, Reset to 3.3V on convertor. I tried to connect with esptool.py, but it did not work. Than I connected RXD to TX and TXD to RX without buffer and esptool was working. I flashed firmware to it. I disconnected GPIO0 and I open serial monitor. I tested 9600b and 115200b and It is unreadable on both speed. On 3.3V serial comunication also not working. What am I doing wrong?

Sorry for my english, I am student and I learn it.

Thanks everyone for help

I open serial monitor. I tested 9600b and 115200b and It is unreadable on both speed

So you get a serial output, but you cannot read it! See here:-

http://www.esp8266.com/viewtopic.php?f=13&t=11727

You may be seeing the initial output at the native speed of 74880 baud. Also if you are using an ESP-7 or ESP12 you didn't mention whether you grounded gpio 15 as well, and pull Reset pin HIGH as well as CH_PD. It is also recommended that gpio 2 be set HIGH as well. Hope that helps.

Hi,

thanks to both of you for answer, I finally found the time and tried change baud rate, but I have same problem. I see the infinitely repeating loop unreadable characters. I use ESP-01 and I also tried to use external supply, but it did not help.

Thanks for help