ESP8266 Community Forum

- Wed Jul 05, 2017 6:12 am #67931 warning: espcomm_sync failed
error: espcomm_open failed
error: espcomm_upload_mem failed
I didnt find any better solution for this issue. I tried up solutions given in forum and the same happens every time. Anyone please help.
Thank ypu

- Thu Jul 06, 2017 1:03 pm #67989

Anyone please help.

Possible problems:

• Incorrectly set used COM-port ("Tools" -> "Port:") or no COM-port selected at all
• Incorrectly set used board ("Tools" -> "Board")
• You're not using an auto-reset and auto-flash board or you forgot to manually press and hold the FLASH-button while pressing RESET-button

But we actually need more info about your setup, because the info you're giving is very little.

Assumption is the mother of all f*ckups. At least: that's what I'm assuming.

- Fri Aug 04, 2017 2:30 am #68813 I am a beginner. I have used the Arduino 1.8.3 IDE for programming my ESP-12 module. I made the connection as shown below:
VCC ---------> 3.3V
TXD0 ---------> Rx of FTDI
RXD0 ---------> Tx of FTDI
GPIO0 ---------> pulled up through 1K resistor
GPIO2 ---------> pulled up through 10K
GPIO15 ---------> pulled down through 10K
RST ---------> pulled up through 10K
EN ---------> pulled up through 10K
Two push buttons are used to pull down RST and GPIO0.
I programmed the basic led blinking program (BUILTINLED) and is working fine. The pin that is blinking now is GPIO1(TXD0). It is working fine. But I cannot reprogram the module.
If I connect the TXD0 to the Rx of serial to usb converter the module itself is not working. ie, if I press the RST button without connecting the TXD0 the module is getting restet (on board blue led blinks), the voltage level at TXD0 is 3.3V. But when I press the RST button after connecting the TXD0, the module is not responding and the voltage level at TXD0 pin drops to about 1.2V.

Please help and thanks in advance.

- Sat Aug 05, 2017 5:27 pm #68863

I programmed the basic led blinking program (BUILTINLED) and is working fine.

It was working the first time, so there's no reason it won't work anymore after that first attempt.

Always use the correct the flash sequence: press and hold FLASH, press RESET, release FLASH.
Also make sure the ESP is connected to a stable and good power supply that's able to supply at least a current of 500mA at 3.3V.

If you're new to the ESP (or any other micro controler): get yourself a proper development board, like a NodeMCU, WeMos, Witty Board, etc.

They're only a dollar or two more expensive than a plain ESP-12, but come with a built in USB -> serial convertor and a nice PCB to work with.
I even use the WeMos D1 for my final projects, since they're cheap (~$2.50), small, have their own USB to serial convertor and support auto-reset and auto-flash (so no hassle anymore getting the thing into programming mode using FLASH and RESET-buttons).

BTW: Are you actually using a plain ESP-12 or is it mounted on a board?

Assumption is the mother of all f*ckups. At least: that's what I'm assuming.