ESP8266 Community Forum

- Fri Mar 20, 2015 12:43 am #12299 https://github.com/nodemcu/nodemcu-flasher/blob/master/README.md
The nodemcu flasher can flash the stock firmware. If you want the latest firmware go to the espressif forums and grab it.

As far as powering the esp8266, the arduino will not source enough amperage to power it, which is probably causing the resets and failure to flash the firmware. Using a logic converter isn't a great way either because the resistors could be limiting the current to the esp8266 as well. As far as the cheap "power bar", many of those on eBay are of dubious quality make sure it has a decent regulator on board, even better if you could measure the current with a multimeter. I recommend you either use a dedicated 3.3v power supply (many cheap ones on eBay canton makes a very good one) or power it with batteries. I doubt you bricked either chip, just make sure you are supplying enough amperage. Also buy a cp2102 it will give you less headaches than flashing from an arduino. A cp2102 and a 3.3v power supply can be had for less than $9 dollars and you can reuse them in other projects.

- Sat Mar 21, 2015 2:17 am #12369

leaving the 8266 in while uploading code to the arduino can kill it

I'm surprised the Arduino UDE doesn't cough a brick. When I try to upload a sketch to my Arduino Uno with the 8266 connected to the Uno's serial port (hint: same as the comm to the PC + IDE) the IDE spits out a message to the effect that the upload has failed.

If that is bricking your 8266, that would seem to be a warning to us all Maybe the 8266 is "seeing" some of the AT+ ... codes in the upload and is trying to action them as they fly past?

It is odd that the 8266 runs normally for a few seconds after it keep resetting itself, though. If it was me, I'd check that the RESET pin is correctly pulled up to +3.3V through a 10k resistor and make sure the supply is decoupled with a 100uF capacitor. If the RESET pin is just floating or there is noise on the +3.3v supply that drops the RESET pin below its threshold voltage, that would cause a chip reset and explain what you are seeing.