Hi, I'm trying to upload sketches to a Wemos D1 mini with Arduino IDE. I get the error "warning: espcomm_sync failed." I know this can be caused by various things. I tried uploading the same sketch to a different Wemos D1 mini using exactly the same settings and it uploads with no errors. So it seems the problem is with that particular D1.
It has power (the LED comes on). There's nothing connected to it (just laptop via micro USB connection). I uploaded code to it in the past with no issues.
I'm no tech guru, and it's not a huge issue if it joins my electronic graveyard, but perhaps there's an amateur friendly fix? A simple way to reset it? (I did try the little reset button but it hasn't seemed to make any difference).
try to reduce upload speed to 115200 bauds
maybe your previous D1 Mini had another variant on CH430 USN chip
Thanks al1fch, I tried all the upload speeds but I get the same error.
I have a development in the troubleshooting. With the 2nd D1 Mini I succesfully uploaded code to it before connecting it to the circuit. Once I connected it to the circuit I tried uploading code and it now gives the same error message as the first D1 mini. When I disconnect it from the circuit and try to upload the code it still gives the same error message. So it's now acting in the same way as the 1st D1 Mini. As if the circuit broke it or changed something on it.
I have a 3rd D1 Mini. The code uploads with no errors and I haven't connected it to the circuit. I'll upload a diagram of my circuit.
Are you simultaneously programming your Wemos via the USB socket and connecting the 5v pin to a 5 volt external power supply ?
I believe you should remove the red ink between the Wemos 5v pin and the bottom red breadboard rail. Anyway, for testing program upload, completely remove the Wemos from the breadboard and have no connections to it apart from the USB.
6v6gt:
Are you simultaneously programming your Wemos via the USB socket and connecting the 5v pin to a 5 volt external power supply ?
I believe you should remove the red ink between the Wemos 5v pin and the bottom red breadboard rail. Anyway, for testing program upload, completely remove the Wemos from the breadboard and have no connections to it apart from the USB.
Yeah, I did have it connected like that when I uploaded the sketch. Thanks for the help, I won't do that again in future. Now I can't upload a sketch to these two D1 Minis, even when they're connected to USB with no other connections. Does anyone know a way to fix them or are they permanently defunct?
