ESP8266 Community Forum

So grounding the D3 pin allows the flasher to work, cool!

I wonder why the LUA flasher can flash the chip without grounding D3 on this module?

A USB connection can have access to other rs232 pins DTR and RTS I suspect the D1 has traces that connect them to the Flash and Reset Pins. The uploader is in control of whether these pins are used and of course the hardware has to use them as well.

Hello

I used ESP-Basic on several WEMOS D1 Minis, without any problems while flashing.
Now I have tree D1 Minis that I can not flash with success.
Response from the flasher (version A69) is:

Uploading 523104 bytes from .\build\4M\ESP8266Basic.cpp.bin to flash at 0x00000000
................................................................................ [ 15% ]
................................................................................ [ 31% ]
................................................................................ [ 46% ]
................................................................................ [ 62% ]
................................................................................ [ 78% ]
................................................................................ [ 93% ]
............................... [ 100% ]


Then I used PUTTY to see the serial Output on startup ... and it shows this:
ets Jan 8 2013,rst cause:2, boot mode:(3,6)
load 0x4010f000, len 1384, room 16
tail 8
chksum 0xef
csum 0xef
csum err
ets_main.c


I tried seperate grounding of D3 while flashing without success.


By the way: Same results when using NODEMCU-clones LOLIN V3

If you are using the version 3 branch you should just wait for the flashing to finish and the esp boot msgs to show up in the flasher window. There is a delay from when it flashes to when it exicutes.