"Guru Meditation Error: Core 0 panic'ed " happens when using "WiFi"

[huaxiaozhong1]

My environment is as below.
esp-wrover-kit, Arduino IDE with selecting board "ESP32 Dev Module" (see viewtopic.php?f=19&t=5002).
When I ran ~/arduino-1.8.5/hardware/espressif/esp32/libraries/WiFi/examples/WiFiClient/WiFiClient.ino, an error was reported saying "Guru Meditation Error: Core 0 panic'ed (IllegalInstruction)".
We could address the issue very accurately. At WiFiClient.ino as attached, all statements related to "WiFi" were commented. Then it could run forever (see 180314-1.log).
If it just ran very few statements related to "WiFi" (see WiFiClient.2.ino), then "Guru Meditation Error: Core 0 panic'ed " occurred (see 180314-2.log).
I think you are able to replace issue with running the same example at your side
Could you help to analyze the issue then?
Thanks!

[huaxiaozhong1]

Hello, have you REPRODUCED the issue? Please notice that the issue happened in a "standard" Arduino example calling "WiFiClient". If it is a real bug with ESP-Wrover_kit dev board, it will really impacts developers' confidence to implement WiFi-related app on the board Thanks!

[ESP_Sprite]

What is your power supply like? WiFi has very short bursts of high power usage, if this makes your power line sag (because you're e.g. powering your development board over USB through an unpowered USB hub or crappy/long USB cable), the flash chip can brown out leading to this issue.

[huaxiaozhong1]

Hi, thank you so much for your rapid and targeted guidance! May I report some updates as below?

1, To fix the issue of power unstability, I went to market and bought a 5V power cable this afternoon. Then connected the cable to our board (see webwxgetmsgimg-2.jpeg attached).
2, From the picture, you could see that a USB cable is connected to the board, as well. Its other port connects to a power-supplied USB HUB, which connects to my laptop then.
3, From the log (180319-2.log attached), looks like that the board, sometimes, could keep working longer than before. For example, it worked for > 30 loops once (the board sleeps 5 seconds for one "loop").
4, As I reported and showed my demo codes last time, the issue doesn't happen when "WiFi.begain" isn't called.
5, You should have the board (ESP-Wrover-Kit) and the Arduino example code (~/arduino-1.8.5/hardware/espressif/esp32/libraries/WiFi/examples/WiFiClient/WiFiClient.ino). So, could you also run the same example with the same board, to see whether the issue exists at your side also?
6, If it is the issue that only exists at the individual board, then may I ask for shipping another board to me? For the new board, you could well test the example code on it before shipping it to me
Thanks again!

[huaxiaozhong1]

Hi, with running codes similar to https://github.com/TwilioDevEd/sync-for ... 2_Sync.ino, our test can go on The issue of "Guru Meditation Error: Core 0 panic'ed" does still exist but not very frequently. Especially after the board boots up for a while, it happens really seldom. So, looks like that you could put the issue to a lower priority now
Thanks for your guidance!