Joseph Bradshaw / ServoIn

Class Library for reading hobby servos and detecting invalid or disconnected channels

Dependents:   MadPulseCntrl Emaxx_Navigation Emaxx_Navigation_Dynamic_HIL Madpulse_Speed_Control_temp ... more

ServoIn Class Library

This class library uses external interrupts with timer functions to read servos pulses on mbed input pins.

ServoIn Library usage example

#include "mbed.h"
#include "ServoIn.h"

DigitalOut led1(LED1);
ServoIn servoIn1(p15);
ServoIn servoIn2(p14);
Serial pc(USBTX, USBRX); // tx, rx

int main() {    
    pc.baud(921600);            //Fast baud rate
        
    while(1) {
        led1 = 1;
        wait(0.05);
        led1 = 0;
        wait(0.05);
        
        pc.printf("servo pulse: CH1=%5dus  CH2=%5dus\r\n", servoIn1.read(), servoIn2.read());        
    }
}

Diff: ServoIn.cpp

Revision:
5:598ccee73ed3
Parent:
4:379f9ab5cb4b
--- a/ServoIn.cpp	Thu Aug 04 15:46:31 2016 +0000
+++ b/ServoIn.cpp	Mon Aug 14 14:51:20 2017 +0000
@@ -48,8 +48,13 @@
     }
     else{
         servoPulse = pulseMeasure.read_us();
-        _interrupt.rise(this, &ServoIn::PulseRead);
-        _pulseFlag = 0;
+        if(servoPulse < this->servoPulseMax){
+            _interrupt.rise(this, &ServoIn::PulseRead);
+            _pulseFlag = 0;
+        }
+        else{
+            _pulseFlag = 1;  //set the pulse input flag
+        }
     }
     _validPulseTimeout.attach(this, &ServoIn::timeoutTest, 0.015); //setup interrupt for 15ms
     _t_state=0;  //re-zero t-state