ESP32 hanging forever

[vtunr_abl]

Hi,

I'm working on a project, and sometimes, the ESP32 is stuck hanging forever.
I checked and no I2C running, no MQTT running, so it seems the full system is stuck.
I tried attaching JTAG when this happens, but I have errors starting it.
I also have all watchdog enable (interrupt, iddle1/0) with panic trigger, and they are not triggered.
A press on the reset button is unlocking everything.

I'm running my code on a WROOM-32 (custom PCB), with ESP-IDF v4.0

So my questions would be :
* What could be happening ?
* Any solution to be able to see what's the system status when this happens ?

[ESP_Sprite]

Hard to say. May be that your program is running in a state that is technically valid but just doesn't output anything... You could hook up a timer or a button to an interrupt and crash the system using that; that should give you a panic and a backtrace or core dump.

[vtunr_abl]

Thanks ESP_Sprite,
I setup an interrupt that will crash the system if button is pressed. I just need to wait now.
I'll update the post once reproduced.

[vtunr_abl]

Hi @ESP_Sprite, since it's hard to reproduce, I wanted to know if there is something specific I could check HW wise when this happens. As it's a custom PCB, we want to rule out design issue.

[ESP_Sprite]

Nothing hardware-wise comes to mind that could cause a symptom like this, sorry... most I can come up with is that you might be able to check the 40MHz crystal, see if it oscillates when the chip is hung like that.

[omer.efrat]

Hey guys,

We are currently experiencing a very similar issue. we have it reproducing only once in a while.
we are running 300 devices for testing this issue and we get approx 2-3 new hang devices every day

We have measured the external crystal to check it's behavior in 3 devices. we got a different result on each one, as follows:




while a working devices behaves as follows:


Does anyone have any idea what this is happening?

Thanks

[ESP_Sprite]

Hard to say... can you tell us more about your design? Schematics, what components do you use, how did you select the crystal / load capacitors, any other relevant information?