Diff: main.cpp

Revision:

0:00eb873ca4c4

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Mon Dec 30 09:17:48 2019 +0000
@@ -0,0 +1,82 @@
+//==================================================
+//Manual and Auto
+//
+//MPU board: mbed LPC1768
+//Multiplexer TC74HC157AP
+//2019/10/13 A.Toda
+//==================================================
+#include "mbed.h"
+
+//==================================================
+#define THRESHOLD_PWM 0.0015
+#define SERVO_PERIOD  0.020
+//==================================================
+
+//Port Setting
+InterruptIn reading_port(p18); 
+DigitalOut mux_switch(p19);
+PwmOut ELE(p21);
+Serial pc(USBTX, USBRX);    //UART
+
+//==================================================
+//Timer valiables
+//==================================================
+Timer ch_time;//timer for calculate pulse width
+
+double measured_pre_pulse=0.0;
+double measured_pulse=0.0;
+
+double pulse_width_ele;
+//=================================================
+//Functions for rising and falind edge interrution
+//=================================================
+//rise edge
+void rising_edge(){
+    ch_time.reset();//reset timer counter
+    measured_pre_pulse=ch_time.read();
+    
+}
+
+//falling edge
+void falling_edge(){
+    measured_pre_pulse=(ch_time.read()-measured_pre_pulse);
+    pc.printf("The pulse width=%f\r\n",measured_pre_pulse);
+    if(measured_pre_pulse>THRESHOLD_PWM){
+        mux_switch=1;
+        }else{
+            mux_switch=0;
+            }
+}
+
+//==================================================
+//Main
+//==================================================
+int main() {
+
+    //UART initialization
+    pc.baud(115200);
+    
+    //Logging starts
+    pc.printf("Reading starts.");
+    
+    //define servo period
+    ELE.period(SERVO_PERIOD);  // servo requires a 20ms period
+    pulse_width_ele=0.001;
+    
+    //timer starts
+    ch_time.start();
+    
+    //declare interrupitons
+    reading_port.rise(rising_edge);
+    reading_port.fall(falling_edge);
+    
+    mux_switch=0;
+    
+    //while
+    while(1) {
+                
+        pulse_width_ele=0.0015;
+        wait(0.05);
+    }//while ends
+    
+}//main ends
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