SYSTEM_EVENT_STA_GOT_IP never received, other units work, Wrover-B defective?

[luisonoff]

-- I also opened same issue on github -- https://github.com/espressif/esp-idf/issues/3244

Hello,
Please help me debug this issue, right now I believe we got a defective Wrover-B module, but don't know how to confirm this.

At my company, Sistel, we are at the final stage of product development using ESP32 as main MCU. We received this week 5 test units, they all work perfect, except one of them is never getting the IP event so it doesn't have internet connection.

Same HW, same SW, same programming method, etc. Looking at the PCB there is no sign of bad solder or anything different from the other units.

We are using Wrover-B module with 8MB flash and 8MB RAM, PCB antenna, soldered on our pcb which has many other components: RTC crystal, SD card, another MCU, RFID, NFC, Eink, battery charger, buzzer, leds controller. And of course a battery, EINK screen, RFID and NFC antennas. Everything else works correctly in every unit.

IDF release version 3.1.3.

Code is propietary so I cannot publicly share it, yet.

Units that work OK receive events:
SYSTEM_EVENT_STA_START
SYSTEM_EVENT_STA_CONNECTED
SYSTEM_EVENT_STA_GOT_IP

Unit that is NOT working just receives:
SYSTEM_EVENT_STA_START
SYSTEM_EVENT_STA_CONNECTED
nothing else

It does not matter in which order I turn them on, or if the other units are on or off.

My first thought was no wifi communication due to bad antenna matching or something, but then I saw STA connected event, that means it is connecting to the Wifi network, right?

Any clue about what could be happening? Is it feasible that I got 1 defective unit of Wrover-B module from just 5 units? (I find this hard to believe, pretty sure you are testing them on fab right?)
How can I better debug this issue or what extra info may you need in order to better understand what is going on?

Thank you very much for your time and support,
Luis Ródenas

[luisonoff]

Added some debug logs to github issue, still no idea of why just one of my 4 units is not getting the IP event but seems to be connecting OK to wifi.

https://github.com/espressif/esp-idf/issues/3244


Any help or hint is much appreciated, thank you. :)

[luisonoff]

We found out the problem!!!
After some investigation we found out our DHCP server in my company was working erratically, not giving IP to some specific MAC addresses, but working ok with the vast majority. No idea why. We have Windows Server 2012, we removed the option of DHCP redundancy and restarted the service and everything seems to be working OK again.

Conclusion: if you are not getting IP event, DHCP in the wifi network may be the cause.