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@@ -89,9 +89,11 @@ as data (http://x.x.x.x/rgb).
                              resolution images as there is not enough memory)
                                            
 GPIO PINS:
-<br>The main io pins available for general use are 13 and 12 (12 must not be high at boot and sd-card needs to be in 1-bit mode),
-<br>14, 2 & 15 should also be available if you are not using the SD Card. 
-<br>You can also use pins 1 and 3 if you do not use Serial. 
+<br>The available pins are very limited on the esp32cam, my best understanding is:
+<br>If using the sd card (must be in 1-bit mode) the main io pins available for general use are 13 and 12 (12 must not be high at boot),
+14, 2 & 15 should also be available if you are not using the SD Card.
+<br>You can also use pins 1 and 3 if you do not use Serial.  Pin 4 is the onboard flash LED which you could remove and use this pin for i/o 
+(but again sd card must be in 1-bit mode if using the sd card)?
 <br>More info: https://randomnerdtutorials.com/esp32-cam-ai-thinker-pinout/
 <br>BTW-You can use an MCP23017 io expander chip on pins 12 and 13 to give you 16 general purpose gpio pins, this requires the adafruit MCP23017 library to be installed.
 <br>Pin 16 is used for psram but you may get away with using it as input for a button etc.?