Comments on: Getting Started with ESP-NOW (ESP32 with Arduino IDE)

By: Sara Santos

Sara Santos — Mon, 04 May 2026 20:46:28 +0000

In reply to Johannes jansen.

You’re welcome.
Regards,
Sara

By: Johannes jansen

Johannes jansen — Mon, 04 May 2026 19:44:58 +0000

Works fantastic on platformio with two freenoveesp32 S3 wroomn ESP32 Now.
Thanks forthis example
Best Regards
Johannes

By: terry

terry — Sun, 26 Apr 2026 22:45:46 +0000

Channels being the same is early on in the discussion. It is commonly known they have to be on the same channel. Default is channel 1 unless you are mixing access point and use as a client(It would then adopt the channel of the other network). Good point to raise again, for those that skip the early parts of this tutorial.

By: Jack

Jack — Sun, 26 Apr 2026 21:39:30 +0000

An exception to having to tell chips what channel to use, is if two or more use wifi and communicate through a router… these will already know the channel because it’s assigned by the router and so can communicate using esp_now. Thus, both of my S3’s running webpages connect easily as they go through the router which assigns them the same channel. But for outlying chips connecting to the router-connected chips over esp-now, these chips do in fact have to be informed of the correct channel. Luckily there’s a good tutorial on doing that on the RandomNerds website.

I HAVE had trouble with comms between chips sitting too close to each other… for whatever reason, the wifi and esp_now comms both work better with a little distance between the chips – only an issue when they’re sitting close on the same hobby table. A chip sitting next to the main chips was dropping around 15% of readings, which problem resolved after I moved one a little further away (a few feet).

By: Sara Santos

Sara Santos — Sun, 26 Apr 2026 20:42:31 +0000

In reply to synnoack.

Hi.

Thanks for letting me know that.
We never had issues with the channels, so I didn’t know that could happen.

Thanks for sharing the solution.

Regards,
Sara

By: synnoack

synnoack — Sun, 26 Apr 2026 19:06:47 +0000

Thanks for all these ESPNow posts. They have helped me a lot.

I would like to add that unlike the sketches in this particular post, you absolutely must set the WiFi channel the same on the “Sender” and the “Receivers”. You do not need to necessarily connect any specific WiFi network, only set some channel. For example:

WiFi.mode(WIFI_STA); WiFi.setChannel(bestChannel);

Where “bestChannel” is one you pick somehow.

If you do not set the channel, it might just happen that it works, but it is just chance. This is exactly what happened to me when my working system was tried in a different building (with different wifi networks), nothing worked very well. In my case, at home the WiFI was on Channel 1. In the other location, I was also connecting to a WiFI network to access a web service, but in doing so the WiFI channel changed to 6. The “Receiver” which did not set a channel was probably defaulting to 1 but the “Sender” was set to the WiFi channel 6. The RSSI I was reading on the “Receiver” was extremely low even sitting right next to the “Sender” (e.g., -87dBm). I suspect there is enough signal getting through (imperfect band pass filters) that I was mistakenly thinking I had a interference problem. It was a uninitialized ESPNow channel number problem all along.

By: John

John — Thu, 12 Mar 2026 02:09:31 +0000

Hi All,
I’d just like to share that, I’ve spent 3 days of scouring the various forums, I’ve interfaced with 3 different AI’s that gave countless sketches (each guarenteed to work) all to the same ending. Not being able to get ESP-NOW to work with an ESP32C3 as a sender and ESP32 D1 mini as a receiver. I did have a working link up until core 3.x came along and broke everything. I also have had ESP32 to ESP32. links running, and probably could still do that but it doesn’t fit the plan of having a battery powered, low power consumpton mpu as a transmitter for a remote sensor.
The C3 worked well in that regard when I had a working test set up and ran for over 3 months on a 3.2v lifepo4 battery. That came to an end when I decided to change the receiving gateway (used to collect sensor data and forward it to an mqtt broker) and needed to change the mac address. After compiling nothing worked again. My point is, why use a protocal that is so sensitive to alteration, and prone to assured failure when the ide core is changed or espressif decides it isn’t interested in fixing it. The method I was using was simply through wifi from ESP to mqtt broker. I thought I’d clear some traffic on the home network by using ESP-NOW to carry some of it. It never worked out. I know many say the C3 works, and mine have, but that was before core 3.x

By: amorfic

amorfic — Tue, 03 Feb 2026 18:59:18 +0000

Hi Sara,
Great tutorial (as usual).
I’ve got a question about add_peer() function – what if I reset (switch power off/on) sender board?
It would try to add peer which has existed already – according espressif docs, function should returned ESP_ERR_ESPNOW_EXIST but ESP_OK (as I understood).
I’ve tested resetting both bards everything works ok, but i’m concerning.
Perhaps You can explain how it works.

By: Jack Rowe

Jack Rowe — Fri, 30 Jan 2026 17:14:21 +0000

Sara,

Does the “2.0 protocol” refer to the chips themselves, or to the firmware? If firmware, how do I update my chips with the 2.0 firmware?

Thanks, Jack Rowe

By: Sara Santos

Sara Santos — Mon, 26 Jan 2026 22:59:41 +0000

In reply to Steve.

That’s a great improvement.
Thanks for letting me know.
Regards,
Sara