It should work with that board.

• Can you copy and paste the exact error message that you see in your Arduino IDE?
• Which board are you selecting in your Arduino IDE?

Thanks!

Thank you.
The watchdog reset the cpu every 10 sec. I could copy the exact message but, the example BLE_SCAN program stucks in init.
So, the board selection is   ESP32 DEV MODULE    and  frequency  40Mhz xtal, flash mode DIO
Am I correct ?

Yes, that board selection should work. But did you try to upload the Blink sketch first? Is that running in your board properly first?

Yes, the blink sketch works fine.

I’ve tried wifiScan it stucks, and the device reboot….

I follow all instructions from course.  See result in monitor:  I added  “setuping” message at begin

:04:11.237 -> Setuping...
09:04:21.327 -> E (10595) task_wdt: Task watchdog got triggered. The following tasks did not reset the watchdog in time:
09:04:21.327 -> E (10595) task_wdt: - IDLE0 (CPU 0)
09:04:21.327 -> E (10595) task_wdt: Tasks currently running:
09:04:21.327 -> E (10595) task_wdt: CPU 0: wifi
09:04:21.361 -> E (10595) task_wdt: CPU 1: IDLE1
09:04:21.361 -> E (10595) task_wdt: Aborting.
09:04:21.361 -> abort() was called at PC 0x400d990f on core 0
09:04:21.361 -> 
09:04:21.361 -> Backtrace: 0x4008c7e0:0x3ffbe160 0x4008ca11:0x3ffbe180 0x400d990f:0x3ffbe1a0 0x40081789:0x3ffbe1c0 0x40132e46:0x3ffb5290 0x40132e95:0x3ffb52b0 0x40133345:0x3ffb52d0 0x4013024d:0x3ffb5370 0x40130522:0x3ffb53f0 0x40130f8a:0x3ffb5440 0x40131de0:0x3ffb5460 0x40132298:0x3ffb5480 0x400d9212:0x3ffb5540 0x400d94c2:0x3ffb5570 0x4010d11d:0x3ffb55a0 0x4010d222:0x3ffb55d0 0x4010d52a:0x3ffb5600 0x4010d6bb:0x3ffb5630 0x4008f8cc:0x3ffb5650 0x4008877d:0x3ffb5690
09:04:21.395 -> 
09:04:21.395 -> Rebooting...
09:04:21.395 -> ets Jun 8 2016 00:22:57
09:04:21.395 -> 
09:04:21.395 -> rst:0xc (SW_CPU_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
09:04:21.395 -> configsip: 0, SPIWP:0xee
09:04:21.395 -> clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
09:04:21.434 -> mode:DIO, clock div:1
09:04:21.434 -> load:0x3fff0018,len:4
09:04:21.434 -> load:0x3fff001c,len:928
09:04:21.434 -> ho 0 tail 12 room 4
09:04:21.434 -> load:0x40078000,len:8424
09:04:21.434 -> ho 0 tail 12 room 4
09:04:21.434 -> load:0x40080400,len:5868
09:04:21.434 -> entry 0x4008069c
09:04:21.805 -> Setuping...

That error is very hard to debug. Are your running the exact WiFiScan sketch that comes with the Arduino IDE without any modifications?

Sometimes when you write a sketch you might do something wrong (coding) that could trigger the watchdog. But using the default example, I really don’t know how it could trigger it.

I also don’t think it’s a power issue, otherwise it would print (brownout error message). It still might be worth it to try with a different USB cable (shorter) or in a different USB port.

Do you have another ESP32 board that you could try this example with?

Just to be sure… Are you using this exact board?

Does it have anything soldered in the “ESP32-WROVER” Option Space?

Solved !
I’ve re-installed ALL . Use Library DEV instead stable. Also, select CPU_Frequency=240 Mhz.
In the document from devkitC_v4, it was noted  40Mhz xtal.
 
Thank you.
 

Thanks for letting me know. To be honest that shouldn’t be necessary and it should work with the other setup…
Regards,
Rui

Also, I was installing ESP32 v1.02 and 1.03rc. With 1.03rc, it works partially, notify and read/write did not work. Connect works.
I’ve re-installed ESP32 1.01 in Arduino, everything works.  It is worrying.  
My conclusion v1.01 is stable, other version are garbage….

I’ve been using only the stable versions (not dev versions) and I’ve also encountered some issues before, but nothing like that. It’s good to know, so if anyone has the same issue, I can help.

Hi guys, is this topic still actual?

I’ve tried all the advices of yours and from several others forums, but still the same result..
I have this model ESP32-DEVKITC-32UE, selected board ESP32 Dev Module.
I can compile and upload the sketch, but then on serial monitor I can see only a garbage.
Help please!

The problem was in between the keyboard and the chair…

Anyway, thanks for your contributions here, it was help full.

Regards
Maxim

I’m glad you made it work Maxim!
Regards,
Rui