esp8266 on wifi serial board and Arduino Uno board

arduino esp8266
Gilad Ravid picture Gilad Ravid · Mar 2, 2016 · Viewed 30.2k times · Source

I bought esp8266 with serial wifi wifi card I connect RX to TX; TX to RX; VCC to VCC; GRD to GRD; I cant communicate with the board not if program mode and not in UART mode; the reset do nothing.

the red led on the board is on.

I connected the wifi serial to Arduino uno board. try to upload sketch i got the following error:

warning: espcomm_sync failed
error: espcomm_open failed
error: espcomm_upload_mem failed

Any help or guides will help me to solve the issue.

Answer

Valentin Grégoire picture Valentin Grégoire · Mar 10, 2016

Since I have had numorous of problems with my ESP8266 modules, this is what I generally watch for:

  • Output is 3.3v
  • Swap over tx and rx. Some boards have them swapped for some reason (searched for days for this!!)
  • When uploading the code, first the code compiles, then the code uploads. During the compile process, keep the reset button (or pin) pressed. As soon as you see the "uploading" status message, you can release it.
  • Make sure the GPIO0 is connected to the ground and (depending on which version you have) the GPIO15 as well.
  • When grounding the GPIO0 and GPIO15, use a resistor for each (between 2K and 10K will do).

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