I have a NodeMCU board with a broken UART module. So I tried to program the esp8266 via an external CP2102 breakout board. I have powered the NodeMCU directly with 3.3V on the 3.3V pin and connected TX/RX/GND of the CP2102 breakout board.
I am able to receive the "ets Jan 8 2013,rst cause:2, boot mode:(3,7)" via the serial monitor of the arduino ide. But I just get an error when I try to program the esp826 with the arduino ide:
warning: espcomm_sync failed error: espcomm_open failed error:
espcomm_upload_mem failed error: espcomm_upload_mem failed
What I am doing wrong? I am pressing Flash, tap reset and release the flash button on the nodemcu board.
Best Answer
If you are powering the esp8266 directly from the 3.3v pin of the CP2102 board, this one doesn't has the enough current (>200mA) to run the esp8266. You must to connect the esp8266 to an external 3.3V power supply which should give more than 400mA.