3 of 3 people found this helpful
The UNO can sample the ADC at over 9,000 Hz, so the problem is not the A/D converter.
The serial port may have a baud rate that is too slow to send data this quickly.
At 9,600 baud the serial port sends about 1 byte per millisecond.
At 115,200 baud it can send about 12 bytes per millisecond.
If you need to go faster, you could try SPI.
4 of 4 people found this helpful
Another thought - You could run some tests - create a sample sketch to JUST read the ADC say, 10,000 times and see how long it takes to execute. Don't print anything to the serial port during that time. That could tell you if the serial port is slowing you down.
You could then also set up your code to only print periodically to the serial port - say only when the value changes by a certain amount; and also every 1-200 ms.
I also found this article that may have some stuff that helps you: https://forum.arduino.cc/index.php?topic=6549.0