[Solved] Updating Your Old Code article example ESPNOW 2-Way Communication code won't compile

Hi everyone,

The example code from Bill’s December 27, 2024, article ESP32 Boards Manager 3 – Updating Your Old Code won’t compile. It has been a while since I played with ESP32s, and in the meantime, Arduino has moved from Boards Manager 2 to 3. I was surprised when Bill's updated version of the ESPNOW code wouldn’t compile. That means I am doing something wrong.

I have an Espressif esp32-s3 devkit c-1 v1.1 I am dealing with. I have uninstalled and reinstalled the Arduino IDE. I have uninstalled and reinstalled the ESP32 board packages. I have tried the ESP32S3 Dev Module board as well as the ESP32 Dev Module with the same results. So, here are the errors:

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]
100 | 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\pritc\AppData\Local\Temp\.arduinoIDE-unsaved202583-22248-1l22m2v.a98t\sketch_sep3a\sketch_sep3a.ino:10:
C:\Users\pritc\AppData\Local\Arduino15\packages\esp32\tools\esp32-arduino-libs\idf-release_v5.5-b66b5448-v1\esp32/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\pritc\AppData\Local\Arduino15\packages\esp32\hardware\esp32\3.3.0\libraries\WiFi
Using library Networking at version 3.3.0 in folder: C:\Users\pritc\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]

I’m sure there is loads of information I have left out, but just ask and I will get it.

Thank you in advance for any advice!