Olimex Support Forum

Microcontrollers => ESP32 => Topic started by: RobLatour on September 08, 2019, 12:58:05 AM

Title: need help with my esp32-poe-iso
Post by: RobLatour on September 08, 2019, 12:58:05 AM
 It appears I now have two fried esp32-PoE-ISO boards.

The first board will do an initial ethernet connect but will not return the ip address (fire SYSTEM_EVENT_ETH_GOT_IP), the second will not even allow me to connect to it to flash it.

I have a program, it's quite simple in what it does, basically, on a trigger it sends a WOL packet out over my home network.  That part is fine.  The source is open and published on github at https://github.com/roblatour/WOL-Olimex-ESP32-PoE-ISO and the project is described at https://hackaday.io/project/166985-wol-with-google-homealexa-ifttt-esp32-poe-iso

The problem I am running into appears to be when I try to also add the use of pin 15 to blink a blue LED (used as a way to report status).

I connected the LED to the ground and pin 15 and set it to high and then low to blink it.  That seemed to work for a while but after that - in both cases - the card seems to become toast.

I'm afraid while I'm not too bad with software, I'm still learning hardware. Any idea in what I am doing wrong?  I've read adding a 1 ohm resistor between the LED and pin 15 may help, but this is getting expensive so before I order another card I thought I would ask here.

Both cards say they are Rev. B.

Thanks in advance
Title: Re: need help with my esp32-poe-iso
Post by: JohnS on September 09, 2019, 01:26:49 AM
Sounds like you need a much bigger resistor and with such a low value have shorted out the port.

John
Title: Re: need help with my esp32-poe-iso
Post by: LubOlimex on September 09, 2019, 09:44:00 AM
Hard to say what happened. You need a resistor, maybe the first got damaged because of this. The 1k is enough, however, so something else is at play here. Tell me:

1) How do you power the board? What equipment exactly?

2) Do you have SD card inserted at the same time as the LED?

3) Can you show us a picture of your hardware setup? Upload it somewhere and give us a link.
Title: Re: need help with my esp32-poe-iso
Post by: JohnS on September 09, 2019, 08:22:42 PM
Seems to be 1 ohm, not 1k ohm...

John
Title: Re: need help with my esp32-poe-iso
Post by: LubOlimex on September 10, 2019, 08:19:16 AM
Quote from: JohnS on September 09, 2019, 08:22:42 PM
Seems to be 1 ohm, not 1k ohm...

John

Oh wow didn't process it right. Well, 1 Ohm is not enough. Try 1K Ohm.
Title: Re: need help with my esp32-poe-iso
Post by: RobLatour on September 12, 2019, 01:44:12 AM
Thank you, I will try 1k and report back.
Title: Re: need help with my esp32-poe-iso
Post by: RobLatour on September 13, 2019, 02:10:12 AM
the 1k ohm resistor is working great!  Thanks again for your help.  Rob