ESP8266 Community Forum

- Tue Jan 10, 2017 8:12 pm #60815 I haven't been able to upload anything to my NodeMCU[ I've tried 6 different usb cables and all but one let the computer see COM 3 as the port for the module. I'm pretty sure I have the right drivers for it (CP2102) and I've tried both Arduino and NodeMCU flasher to upload something to the module and neither work. I've also put it into flash mode each time and still nothing. I'm wondering if my module is bricked. I plugged the board into my mac and ran this in terminal.

Jeremys-MBP:~ Jeremy$ sudo cu -l /dev/tty.SLAB_USBtoUART -s 76800 Connected.
ets Jan 8 2013,rst cause:2, boot mode:(3,7)
load 0x40100000, len 1856, room 16 tail 0 chksum 0x63 load 0x3ffe8000, len 776, room 8 tail 0 chksum 0x02 load 0x3ffe8310, len 552, room 8 tail 0 chksum 0x79 csum 0x79
2nd boot version : 1.5 SPI Speed : 40MHz SPI Mode : DIO SPI Flash Size & Map: 32Mbit(512KB+512KB) jump to run user1 @ 1000
rf[112] : 03 rf[113] : 00 rf[114] : 01
SDK ver: 1.5.4(baaeaebb) compiled @ May 17 2016 19:23:54 phy ver: 972, pp ver: 10.1
?????U? ???uT?.E?B*KVQ??ԪTWT

after a couple seconds nothing happened so I clicked the reset button and thats when everything you see above was populated. Anyone have any ideas?

Last edited by Hodograph on Wed Jan 11, 2017 5:50 pm, edited 1 time in total.

- Wed Jan 11, 2017 4:39 pm #60850 A Few Questions
During Power up, do you get a flicker of the Blue LED?
when you try and re-flash it, do you get a flicker on the Blue LED?
Do you have another unit you can test with to verify FTDI and power supply/cables/other things
I beat my head for awhile on a unit I thought was a brick and it was a bad jumper wire... LOL

- Wed Jan 11, 2017 5:45 pm #60854

During Power up, do you get a flicker of the Blue LED? - See more at: posting.php?mode=reply&f=160&t=13291#sthash.WeH3jXuE.dpuf

When I power up the device, and when I reset it, the blue LED flashes once.

when you try and re-flash it, do you get a flicker on the Blue LED? - See more at: posting.php?mode=reply&f=160&t=13291#sthash.WeH3jXuE.dpuf

Whenever I try to flash it through the NodeMCU flasher the blue light consistently flickers. When I try and upload through the arduino IDE and through esptool.py the blue light flashes 3 times and then the upload/flash fails.

Do you have another unit you can test with to verify FTDI and power supply/cables/other things - See more at: posting.php?mode=reply&f=160&t=13291#sthash.WeH3jXuE.dpuf

No, but I did just buy this pair so I can test this. I did try 8 different usb cables, only one the computer was unable to detect a COM port, the other 7 resulted in the problem I posted about. I have also tried this on 2 different windows machines on both USB 2.0 and 3.0 ports as well as a macbook pro that only has USB 3.0 ports.

- Thu Jan 12, 2017 9:41 am #60891 UPDATE: I followed these instructions and was able to flash firmware successfully to the module, but as soon as I disconnect after flashing the same issues are still present where I can't upload anything to the module via any tool (nodemcu flasher, arduino, esptool). Not sure if theres something I'm missing here or what I'm doing wrong because it works when I have the gpis pins connected but not after I disconnect.