78678
Servo.cpp@4:cbc67535aa7b, 2020-11-04 (annotated)
- Committer:
- fishzhang
- Date:
- Wed Nov 04 02:49:15 2020 +0000
- Revision:
- 4:cbc67535aa7b
- Parent:
- 2:8995c167f399
1
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
simon | 0:24148c673250 | 1 | #include "Servo.h" |
simon | 0:24148c673250 | 2 | #include "mbed.h" |
simon | 0:24148c673250 | 3 | |
simon | 0:24148c673250 | 4 | static float clamp(float value, float min, float max) { |
simon | 0:24148c673250 | 5 | if(value < min) { |
simon | 0:24148c673250 | 6 | return min; |
simon | 0:24148c673250 | 7 | } else if(value > max) { |
simon | 0:24148c673250 | 8 | return max; |
simon | 0:24148c673250 | 9 | } else { |
simon | 0:24148c673250 | 10 | return value; |
simon | 0:24148c673250 | 11 | } |
simon | 0:24148c673250 | 12 | } |
simon | 0:24148c673250 | 13 | |
simon | 0:24148c673250 | 14 | Servo::Servo(PinName pin) : _pwm(pin) { |
simon | 0:24148c673250 | 15 | calibrate(); |
simon | 0:24148c673250 | 16 | write(0.5); |
simon | 0:24148c673250 | 17 | } |
simon | 0:24148c673250 | 18 | |
simon | 0:24148c673250 | 19 | void Servo::write(float percent) { |
simon | 0:24148c673250 | 20 | float offset = _range * 2.0 * (percent - 0.5); |
simon | 0:24148c673250 | 21 | _pwm.pulsewidth(0.0015 + clamp(offset, -_range, _range)); |
simon | 0:24148c673250 | 22 | _p = clamp(percent, 0.0, 1.0); |
simon | 0:24148c673250 | 23 | } |
simon | 0:24148c673250 | 24 | |
simon | 0:24148c673250 | 25 | void Servo::position(float degrees) { |
simon | 0:24148c673250 | 26 | float offset = _range * (degrees / _degrees); |
simon | 0:24148c673250 | 27 | _pwm.pulsewidth(0.0015 + clamp(offset, -_range, _range)); |
simon | 0:24148c673250 | 28 | } |
simon | 0:24148c673250 | 29 | |
simon | 0:24148c673250 | 30 | void Servo::calibrate(float range, float degrees) { |
simon | 0:24148c673250 | 31 | _range = range; |
simon | 0:24148c673250 | 32 | _degrees = degrees; |
simon | 0:24148c673250 | 33 | } |
simon | 0:24148c673250 | 34 | |
simon | 0:24148c673250 | 35 | float Servo::read() { |
simon | 0:24148c673250 | 36 | return _p; |
simon | 0:24148c673250 | 37 | } |
simon | 0:24148c673250 | 38 | |
simon | 0:24148c673250 | 39 | Servo& Servo::operator= (float percent) { |
simon | 0:24148c673250 | 40 | write(percent); |
simon | 0:24148c673250 | 41 | return *this; |
simon | 0:24148c673250 | 42 | } |
simon | 0:24148c673250 | 43 | |
simon | 0:24148c673250 | 44 | Servo& Servo::operator= (Servo& rhs) { |
simon | 0:24148c673250 | 45 | write(rhs.read()); |
simon | 0:24148c673250 | 46 | return *this; |
simon | 0:24148c673250 | 47 | } |
simon | 0:24148c673250 | 48 | |
simon | 0:24148c673250 | 49 | Servo::operator float() { |
simon | 0:24148c673250 | 50 | return read(); |
simon | 0:24148c673250 | 51 | } |