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README.md

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 ## ESP32Cam-demo sketch for use with the Arduino IDE 
 
+Note: the new v3 of the esp32 board manager has kindly changed a lot of stuff resulting in a lot of sketches no longer working :-( <br>
+I have now updated the sketch to work with both.   [more info here](https://docs.espressif.com/projects/arduino-esp32/en/latest/migration_guides/2.x_to_3.0.html) <br>
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 I show in this sketch how to use the esp32cam as easily as possible.  Everything I learn I try to add to it, please let me know if you have anything which you think can be added or changed to improve it - I am not a professional programmer so am sure there is plenty of room for improvement... <br>
 This sketch has got a bit larger than I anticipated but this is just because it now has so many individual demonstrations of ways to use the camera, I have tried to make each part as easy to follow as possible with lots of comments etc.. <br>
 The camera is not great quality and very poor in low light conditions but it is very cheap (around £5 each if buying several) and I think has lots of potential for interesting applications. <br>