ESP32 Forum

Hi,

I want to send UDP multicasts from ESP32 AP to a mobile phone.
I used the udp_multicast example and changed it to AP, but a lot of multicast messages from the AP to the phone were lost (from the phone to the AP it works fine).
I saw on another topic that Wi-Fi modem sleep should be disabled, but it still doesn't work.

Does anyone have a code for supporting multicasts in ESP AP?
I also use AT commands, is there a way to send multicasts using AT command?

Thanks a lot!

Hi almoniplo,

Sorry for the slow reply.

almoniplo wrote: ↑

Mon Jan 06, 2020 11:58 am

I used the udp_multicast example and changed it to AP, but a lot of multicast messages from the AP to the phone were lost (from the phone to the AP it works fine).

I have some questions to help debug this:

How many multicast packets were you sending, and how often?
What size were the packets?
Does the sendto() function ever return an error?

What proportion of packets are being lost between AP and phone? Is there any pattern?

Hi,

Thanks for the reply.

The answers for your questions are:
1. I sent few hundreds of messages. One every second.
2. The packets were about 30 bytes.
3. sendto() never returned an error.
4. 90% of the packets are lost, and I didn't succeed to find any pattern.

It would be great if someone has some code that works