Problems with communications using arduino IDE and ESP3

[molBR123]

So I was testing my esp32 normally, doing the simple stuff, and I wanted to test one of its wifi examples, most specifically the "SimpleWifiServer". So I uploaded it on the board and now I cant upload anything else on the board... the blue led that was always blinking dosent blink anymore and I dont know what to do, any thoughts?

I am using ubuntu 16.04 as operating system

[tele_player]

Does the IDE show errors when attempting to upload a new sketch?
Does your esp32 have two push buttons?

[RustyShackleford]

I've had a very similar experience (from Mac OSX). ESP32 board was working fine for simple stuff. But after I tried SimpleWifiServer the first time, I was no longer able to upload another sketch (got message "could not open port /dev/cu.SLAB_USBtoUART"). But if I then move to another USB port, or another computer, I can upload a benign (not attempting wifi) sketch. However, the port from which I'd attempted to load SimpleWifiServer would no longer recognize the ESP32 (and /dev/cu.SLAB_USBtoUART does not appear). I've tried resetting the USB ports using the Mac's SMC reset procedure, and also resetting the PRAM/NVRAM, to no avail. It's tempting to think I fried the USB port, but thumb drives still work in it.

It's been suggested that the wifi-specificness of the problem suggests it has to do with the ESP32 drawing a lot more power when wifi is turned on. I plan to purchase a powered (with AC adapter) USB hub and see if that works better. Meanwhile, I'm still trying to get my USB ports back to normal ...

[RustyShackleford]

I've become fairly convinced that power is my problem, and very likely yours. Using a shorter & fatter USB cable seems to have helped a lot, though it surely doesn't work on all my USB ports, but it's been suggested (by someone who seems to know what they're talking about) that this could be due to driver issues and/or different handling of power by different ports (those on back of monitor as opposed to ones on tower, that kind of thing).

Anyhow, I'd try a powered (w/ separate AC adapter) USB hub and/or a battery and/or a better cable, if I were you. Good luck.

It'd be nice if Espressif clued people in that turning on Wifi could create issues like this.

[RustyShackleford]

Added 1220mah battery. Problem is gone.