See '20231110-pc-arduino-read-ac' for the code used in this experiment.
Common baud rates are: 9600, 19200, 38400, 57600, 115200
Test 1: 1 Hz sine wave, 9600 baud serial communicarion, 1000 values on X-axis

Test 2: 10 Hz sine wave, 9600 baud serial communicarion, 1000 values on X-axis

Test 3: 10 Hz sine wave, 19200 baud serial communicarion, 1000 values on X-axis

Test 4: 10 Hz sine wave, 38400 baud serial communicarion, 2000 values on X-axis

Test 5: 10 Hz sine wave, 115200 baud serial communicarion, 2000 values on X-axis
Test 6: 10 Hz sine wave, 921600 baud serial communicarion, 2000 values on X-axis

Can I achieve higher baud rates if I do not convert to float on the Arduino? Yes!
Test 7: 40 Hz sine wave, 921600 baud serial communicarion, 2000 values on X-axis
(I disabled the Y-axis since it now shows values between 0 and 1023)

For this last one this was the Arduino code:
void setup() {
Serial.begin(921600);
}
void loop() {
Serial.println(analogRead(A0));
}Idea: maybe it can go even faster when I cast to short?