Can't flash ESP8266 anymore (NodeMCU) So I've been happily making away with these nodeMCU boards now for a while but I came across a strange issue when updating some code on my board.The problem was that I couldn't flash anymore with Arduino's IDE (OR the NodeFlasher tool)

The error I was getting in Arduino's IDE was:

warning: espcomm_send_command: didn't receive command response
warning: espcomm_send_command(FLASH_DOWNLOAD_BEGIN) failed


I tried flashing over all the memory with the flash tool but that didn't work, I also tried connecting D3 to 3.3v output, that did nothing. I've also tried holding the flash button down while flashing without any effect.
The fix ended up being to use a 220ohm resistor between D3 and GND (It has been pointed out, though I haven't tested it, that just wiring D3 to ground on startup should have the same effect). Then unplugging the USB cable, plugging it back in, then flashing the blink program to test. That got it going. I tried a 10kohm resistor too per some documentation I read but that didn't end up working. Wanted to post in case someone else stumbled on this issue. 

Source

GitHub Issue

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