dmadison
commented
3 years ago Hi Adrian. A few questions:
- Are those values outside the range of what you would normally expect? What range are you expecting?
- What is your wiring setup? How long are your wires?
- Have you inspected the PWM pulse with an oscilloscope to rule out a hardware issue?
- What board are you using?
In general extreme values that are well outside of the angle range are caught by the library and ignored. Only values that are within the 'legitimate' pulse window (500 - 2500 µs) will be reported, so it's possible that this is an issue with the command signal and not the library.
I don't understand what you're trying to demonstrate with the example you've shared. Testing with an Uno and 3" jumpers I just get '0' in the serial console constantly, as expected.
Maybe try something like this:
#include <ServoInput.h>
#include <Servo.h>
ServoInputPin<2> servoIn;
Servo servo;
const unsigned long ReportFreq = 5000;
unsigned long lastReport = 0;
int lastAngle = 90;
void setup() {
Serial.begin(115200);
servo.attach(4);
servo.write(lastAngle);
delay(100); // wait for initial angle read
}
void loop() {
int angle = servoIn.getAngle(); // get angle of servo (0 - 180)
if((angle == 0 || angle == 180) && angle != lastAngle) {
Serial.print("!!! Angle irregularity: ");
Serial.print(angle);
Serial.print(" @ t");
Serial.print(millis());
Serial.println();
lastReport = millis();
}
else if(millis() - lastReport >= ReportFreq) {
unsigned long t = millis();
Serial.print("No issues: t");
Serial.print(t - ReportFreq);
Serial.print(" - t");
Serial.print(t);
Serial.print(" (");
Serial.print(angle);
Serial.print(")");
Serial.println();
lastReport = t;
}
lastAngle = angle;
}With a loopback wire that should return 90 or close to it, and will report an issue if the angle is read at either 0 or 180.
AdrianTschannen
Hi Using ServoInput in combination with other functions, from time to time the function "servo1.getAngle()" delivers wrong values in a row: 0's or 180's. One possible reason could be, that the extreme values come due to other interrupt routines, that interferes with ServoInput. I bypassed this problem by simply not using the values 0 or 180. These extreme values are not relevant for my application.
Here is my simple code example:
include
include
ServoInputPin<0> servo1; ServoInputPin<1> servo2;
Servo myservo1; // create servo object to control a servo Servo myservo2; // create servo object to control a servo
void setup() { Serial.begin(115200); myservo1.attach(4); // attaches the servo on pin 9 to the servo object myservo2.attach(5); // attaches the servo on pin 10 to the servo object
}
void loop() { int angle1 = servo1.getAngle(); // get angle of servo (0 - 180) int angle2 = servo2.getAngle(); // get angle of servo (0 - 180)
if (!((angle1==180)or(angle1==0))){myservo1.write(angle1);} else {Serial.println(angle1);} // sets the servo position according to the scaled value if (!((angle2==180)or(angle2==0))){myservo2.write(angle2);} else {Serial.println(angle2);} // sets the servo position according to the scaled value
}