Urgent: Mongoose hangs board on startup, Arduino does not

General
1

To build a product, I had been working with an ESP32 dev board to prototype firmware, and I noticed that it would not start when powered up. I assumed this was a hardware issue with the board. This failure happens reliably.

I just got my first prototype board for my project, and it exhibited the same behavior and I listed it as a hardware bug. However, I then had a reason to load an Arduino application and, low and behold, the board starts fine when powered up. Reliably.

So this appears to be a Mongoose issue. I wrote a very stripped down C++ application that just starts two timers that just print to te serial port. If I reboot the board using the ctrl-U in mos it reboots. If I just power it up it hangs and does not even answer the reset button. It only starts with ctrl-U.

This hardware uses the ESP32-WROOM-32U module.

Is this something wrong in my app, or maybe a known issue? I absolutely must fix this and would really appreciate some guidance.

Thanks…

2

Sorry, I am newbie and my English skills are not perfect.
I don’t get what you want to do? How you want to see anything when you power up ESP? Without console? When you send ‘mos console’ it restarts and you can see what’s going on. If you just power it up from external source (even USB) you can see nothing.

3

Thank you for the reply. The problem is that the application does not run when I power the board up. This is true whether I power it up from the USB-C port or the 12VDC input port. It’s very strange, but an Arduino sketch works fine.

4

If you did everything OK, it should start automatically after power it up, but you can not see this.
Probably Arduino refresh console in some way.

5

Hello Jim,
I believe the issue you are facing has nothing to do with the code your esp is running. The issue is on the windows software side of the mos tool. I think its due to the handling of com port.
The esp will execute the code as you power up your device. If you are sceptical about the issue, try something which does not require a console. For example , try blinking the onboard led on the esp development board. You will see it works as soon as you give power to the board.

6

Thanks, that’s just what I’m trying to do now. Unfortunately my LEDs are interfaced to the ESP32 via an expander board, and I’m having trouble getting that to work under Mongoose (made a separate post). As you say, if I can write a little blink app that starts when I power up then all will be good.

If it matters, I’m using a Mac.

Thanks again, I’ll report back after I get this test to work.

7

You guys were quite right about this, thanks very much. Big relief.