ESP8266 Community Forum

- Sun Sep 20, 2015 7:42 pm #29530 I've been using Kolban's The ESP8266 Book as a launching point into ESP8266 projects. For the moment, my goal is to use the Arduino IDE for programming the ESP8266 modules I have.

Using the circuit schematic on on page 24, I'm having no luck. The Arduino IDE gives me:

Code: Select allwarning: espcomm_sync failed
error: espcomm_open failed

The reset and program (ie. GPIO0 gets pulled low) buttons seem to work. Holding down the program button and then clicking the reset button seems to reset it, and it comes back with the blue LED lit up. In that state, if I connect via serial, it spews an endless line of garbage on UART0.

Is there a recommended minimal circuit for uploading code to a module? I'll try some of the simpler circuits in Kolban's book, but I'm also seeing some that use the UART adapters RTS and DTR signals. Automatic reboots before and after uploading would be nice, but I'd best start simple.

Last edited by Rural on Sun Sep 20, 2015 7:53 pm, edited 1 time in total.

- Sun Sep 20, 2015 7:52 pm #29531 Since the schematic on page 24 is perfect, I suspect that you get continuous resets probably caused by unstable power supply. What kind of power supply are you using ?
Do you have a big capacitor such 470uF on power lines nearby the ESP ?

- Sun Sep 20, 2015 7:57 pm #29532 I'm using an MB102 being fed by a 9v/500ma wal-wart AC-DC adapter. No 470uF capacitor, but I'll give that a try.

My suspicion is that I've misimplemented Korban's schematic.

Since the schematic on page 24 is perfect, I suspect that you get continuous resets probably caused by unstable power supply. What kind of power supply are you using ?
Do you have a big capacitor such 470uF on power lines nearby the ESP ?

- Sun Sep 20, 2015 8:00 pm #29533 The capacitor is really needed.
ESP is so susceptible that only 6 inch of wire for power supply without capacitor and it will choke.