Comments on: ESP32: ESP-NOW Web Server Sensor Dashboard (ESP-NOW + Wi-Fi)

By: Mickey

Mickey — Fri, 24 Oct 2025 07:57:52 +0000

In reply to Dan. Thanks!

By: Sara Santos

Sara Santos — Sat, 18 Oct 2025 10:07:22 +0000

In reply to Dusan.

That’s great!
Regards,
Sara

By: Dusan

Dusan — Fri, 17 Oct 2025 14:15:20 +0000

In reply to Stéphane Calderoni. Dear Sir, Thanks to RNT and such willing people without any claim to any reward like you, even a pensioner like me, whose head is more leaky than a sieve :), can start IT projects. Many thanks.

By: Steve

Steve — Sun, 24 Aug 2025 23:26:24 +0000

In reply to Drakot Kalgor. I just use a separate dedicated ESP8266/32 to send data in emails or to web based servers etc. simply by using espserial between the ESP_NOW device and the WiFi device. 4 bucks is cheaper than any headaches wrestling with ESP_NOW and WiFi on the same device. (Or maybe I'm just lazy to learn how to it right. :-)

By: Sara Santos

Sara Santos — Mon, 11 Aug 2025 11:14:57 +0000

In reply to Dan.

Hi.
You can downgrade to the previous ESP32 core version or use:

void OnDataSent(const wifi_tx_info_t *mac_addr, esp_now_send_status_t status) {

Instead of
void OnDataSent(const uint8_t *mac_addr, esp_now_send_status_t status) {

There were some breaking changes in ESPNOW in the latest version of ESP32 3.3.0.

We’re waiting a few more days to see if the developers will change anything else before updating all our ESP-NOW sender codes.

Regards,
Sara

By: Dan

Dan — Wed, 06 Aug 2025 17:16:17 +0000

this fixed it:

//esp_now_register_send_cb(OnDataSent);
esp_now_register_send_cb((esp_now_send_cb_t)OnDataSent);

By: Dan

Dan — Wed, 06 Aug 2025 16:45:37 +0000

Now it doesn't compile. I pulled up the Arduino IDE and it did some updates. Here's the error msg: :\Users\raweg\dev\Ardiuno\sender_board_2\sender_board_2.ino: In function 'void setup()': C:\Users\raweg\dev\Ardiuno\sender_board_2\sender_board_2.ino:132:28: error: invalid conversion from 'void ()(const uint8_t, esp_now_send_status_t)' {aka 'void ()(const unsigned char, esp_now_send_status_t)'} to 'esp_now_send_cb_t' {aka 'void ()(const wifi_tx_info_t, esp_now_send_status_t)'} [-fpermissive] 132 | esp_now_register_send_cb(OnDataSent); | ^~~~~~~~~~ | | | void ()(const uint8_t, esp_now_send_status_t) {aka void ()(const unsigned char, esp_now_send_status_t)} In file included from C:\Users\raweg\dev\Ardiuno\sender_board_2\sender_board_2.ino:7: C:\Users\raweg\AppData\Local\Arduino15\packages\esp32\tools\esp32-arduino-libs\idf-release_v5.5-b66b5448-v1\esp32c3/include/esp_wifi/include/esp_now.h:185:54: note: initializing argument 1 of 'esp_err_t esp_now_register_send_cb(esp_now_send_cb_t)' 185 | esp_err_t esp_now_register_send_cb(esp_now_send_cb_t cb); | ~~~~~~~~~~~~~~~~~~^~ Using library WiFi at version 3.3.0 in folder: C:\Users\raweg\AppData\Local\Arduino15\packages\esp32\hardware\esp32\3.3.0\libraries\WiFi Using library Networking at version 3.3.0 in folder: C:\Users\raweg\AppData\Local\Arduino15\packages\esp32\hardware\esp32\3.3.0\libraries\Network exit status 1 Compilation error: invalid conversion from 'void ()(const uint8_t, esp_now_send_status_t)' {aka 'void ()(const unsigned char, esp_now_send_status_t)'} to 'esp_now_send_cb_t' {aka 'void ()(const wifi_tx_info_t, esp_now_send_status_t)'} [-fpermissive]

By: Dan

Dan — Wed, 28 May 2025 01:19:14 +0000

I messed around with the esp-idf espnow example for a day and a half and couldn’t figure out how to send the data or read it. I got this example going in about an hour. I didn’t have a DHT sensor so I had the senders pump out some sample values, incrementing them in the loop. This works great.

By: Tomerbt

Tomerbt — Sat, 12 Apr 2025 15:20:01 +0000

In reply to Sara Santos.

I get the value from the receiver using ESP-NOW. Regarding what you mentioned, it is not accurate because when I am connected to the AP I do get the RSSI between the two boards, but when I disconnect I get different values and I can’t figure out the problem. I have attached a link to the forum where I posted the problem, the codes appear there, maybe it can help, I am really desperate.

https://esp32.com/viewtopic.php?t=45224

By: Tomerbt

Tomerbt — Sat, 12 Apr 2025 14:12:53 +0000

https://esp32.com/viewtopic.php?t=45224