I ordered this from the US warehouse which was a little more expensive but shipping was quick. i was worried that i had been sent a defective model because it would not turn on. i could not send or get serial commands (AT commands) either. when i almost lost hope, i had found that i had to keep GPIO15 to ground. I then researched and found the way to turn in on in firmware flash mode to load a sketch from the Arduino IDE. I now run a bipolar stepper motor using this module, and a L293D... and all through wifi... pretty awesome if you ask me. I plan to order more but i am worried now because of all the bad luck that people have been posting about in the reviews. i hope that their module is not defective and that they can resolve a wiring problem i had. here is my wiring. Using: PL2303HX USB To RS232 TTL (only has Grnd, 3.3v, 5v, Rx, Tx Pins) Using the 3.3v in the PL2303HX as power source is sufficient for me. ------------ *CH_PD and Vcc pins to 3.3V *PGIO15 and GRND pins to Ground *Cross Rx with Tx *Cross Tx with Rx To flash sketch, once above is connected, 1) connect GPIO0 (zero) and RST pins to ground. 2) connect PL2303HX USB to computer with the Arduino IDE (See https://github.com/esp8266/arduino) ensure correct COM port etc. 3) disconnect the RST from ground wait 1 second, disconnect GPIO0 from ground 4) quickly compile the sketch to send to ESP-12E. 5) done! there are many instructions in youtube. I hope this helps anyone having trouble.

I ordered this from the US warehouse which was a little more expensive but shipping was quick. i was worried that i had been sent a defective model because it would not turn on. i could not send or get serial commands (AT commands) either. when i almost lost hope, i had found that i had to keep GPIO15 to ground. I then researched and found the way to turn in on in firmware flash mode to load a sketch from the Arduino IDE. I now run a bipolar stepper motor using this module, and a L293D... and all through wifi... pretty awesome if you ask me. I plan to order more but i am worried now because of all the bad luck that people have been posting about in the reviews. i hope that their module is not defective and that they can resolve a wiring problem i had. here is my wiring. Using: PL2303HX USB To RS232 TTL (only has Grnd, 3.3v, 5v, Rx, Tx Pins) Using the 3.3v in the PL2303HX as power source is sufficient for me. ------------ *CH_PD and Vcc pins to 3.3V *PGIO15 and GRND pins to Ground *Cross Rx with Tx *Cross Tx with Rx To flash sketch, once above is connected, 1) connect GPIO0 (zero) and RST pins to ground. 2) connect PL2303HX USB to computer with the Arduino IDE (See https://github.com/esp8266/arduino) ensure correct COM port etc. 3) disconnect the RST from ground wait 1 second, disconnect GPIO0 from ground 4) quickly compile the sketch to send to ESP-12E. 5) done! there are many instructions in youtube. I hope this helps anyone having trouble.

I ordered this from the US warehouse which was a little more expensive but shipping was quick. i was worried that i had been sent a defective model because it would not turn on. i could not send or get serial commands (AT commands) either. when i almost lost hope, i had found that i had to keep GPIO15 to ground. I then researched and found the way to turn in on in firmware flash mode to load a sketch from the Arduino IDE. I now run a bipolar stepper motor using this module, and a L293D... and all through wifi... pretty awesome if you ask me. I plan to order more but i am worried now because of all the bad luck that people have been posting about in the reviews. i hope that their module is not defective and that they can resolve a wiring problem i had. here is my wiring. Using: PL2303HX USB To RS232 TTL (only has Grnd, 3.3v, 5v, Rx, Tx Pins) Using the 3.3v in the PL2303HX as power source is sufficient for me. ------------ *CH_PD and Vcc pins to 3.3V *PGIO15 and GRND pins to Ground *Cross Rx with Tx *Cross Tx with Rx To flash sketch, once above is connected, 1) connect GPIO0 (zero) and RST pins to ground. 2) connect PL2303HX USB to computer with the Arduino IDE (See https://github.com/esp8266/arduino) ensure correct COM port etc. 3) disconnect the RST from ground wait 1 second, disconnect GPIO0 from ground 4) quickly compile the sketch to send to ESP-12E. 5) done! there are many instructions in youtube. I hope this helps anyone having trouble.

I have three of these and they work great. The only problem is that GPIO 4 and 5 are mislabled. I believe some the E series have 4 and 5 swapped so this is likely just a labeling problem. I'm quite happy with this item and just bought three more.

I have three of these and they work great. The only problem is that GPIO 4 and 5 are mislabled. I believe some the E series have 4 and 5 swapped so this is likely just a labeling problem. I'm quite happy with this item and just bought three more.

I have three of these and they work great. The only problem is that GPIO 4 and 5 are mislabled. I believe some the E series have 4 and 5 swapped so this is likely just a labeling problem. I'm quite happy with this item and just bought three more.