Diff: main.cpp

Revision:

3:5edb1ea41029

Parent:

2:b5b8bda0bcda

--- a/main.cpp	Sat Feb 17 15:40:57 2018 +0000
+++ b/main.cpp	Sat Feb 17 17:26:47 2018 +0000
@@ -3,9 +3,9 @@
 
   EXAMPLE DESCRIPTION
 
-  Uses two buttons connected to PA_0 - plus and PA_1 - minus with pull up 
-  resistors. On PA_8 is PWM output with variable duty cycle (DC) and frequncy of
-  500 Hz. DC can be changed true buttons. On press of button DC is incremented 
+  Uses two buttons connected to PA_0 - plus and PA_1 - minus with internal pull 
+  up resistors. On PA_8 is PWM output with variable duty cycle (DC) and frequncy 
+  of 500 Hz.DC can be changed true buttons. On press of button DC is incremented 
   or decremented by 0.01. Interrupt is attached to falling edge on appropriate
   pin and process of incrementation/decrementation is driven throu this
   interrupt. Programm also demonstrates auto incrementation/decrementation while
@@ -20,7 +20,7 @@
   
 *******************************************************************************/
 
-InterruptIn buttonPlus(PA_0); // deffition of sinterrupt
+InterruptIn buttonPlus(PA_0); // deffition of interrupt
 InterruptIn buttonMinus(PA_1); // deffition of interrupt
 
 PwmOut PWM(PA_8); // definition of PWM pin
@@ -29,8 +29,6 @@
 
 Ticker tick; // Ticker definition
 
-Serial pc(PB_6, PB_7, 9600); // Serial port definition
-
 bool autoIncrement=false; // true - do autoincrement
                           // false - do not autoincrement
 
@@ -45,10 +43,10 @@
     plus=true; // incrementation
     if (PWM.read()+0.01 <= 1) {
         PWM.write(PWM.read()+0.01); 
-        pc.printf("Presed plus button. DC: %f.\n",PWM.read());
+        printf("Presed plus button. DC: %f.\n",PWM.read());
     }else{
         PWM.write(1);
-        pc.printf("Presed plus button. Already maximum DC.\n");
+        printf("Presed plus button. Already maximum DC.\n");
     }
 }
 
@@ -59,7 +57,7 @@
     tim.stop();
     tim.reset();
     autoIncrement=false;
-    pc.printf("Plus button released.\n");
+    printf("Plus button released.\n");
 }
 
 // called after falling edge on PA_1
@@ -70,10 +68,10 @@
     plus=false; // decrementation
     if (PWM.read()-0.01 >= 0) {
         PWM.write(PWM.read()-0.01);
-        pc.printf("Presed minus button. DC: %f\n",PWM.read());
+        printf("Presed minus button. DC: %f\n",PWM.read());
     }else{
         PWM.write(0);
-        pc.printf("Presed minus button. Already minimum DC.\n");
+        printf("Presed minus button. Already minimum DC.\n");
     }
 }
 
@@ -84,7 +82,7 @@
     tim.stop();
     tim.reset();
     autoIncrement=false;
-    pc.printf("Minus button released.\n");
+    printf("Minus button released.\n");
 }
 
 
@@ -110,6 +108,10 @@
     buttonPlus.rise(&releasedPlus);
     buttonMinus.rise(&releasedMinus);
     
+    // internal pull ups
+    buttonPlus.mode(PullUp);
+    buttonMinus.mode(PullUp);
+    
     // set ticker interrupt
     tick.attach(&checkTimer,0.01);
     
@@ -117,11 +119,11 @@
         // check if auto increment/decrement
         if(autoIncrement && plus && PWM.read()+0.01 <= 1){
             PWM.write(PWM.read()+0.01);
-            pc.printf("Autoincrement. DC: %f.\n",PWM.read());
+            printf("Autoincrement. DC: %f.\n",PWM.read());
         }
         else if(autoIncrement && !plus && PWM.read()-0.01 >= 0){
             PWM.write(PWM.read()-0.01);
-            pc.printf("Autodecrement. DC: %f.\n",PWM.read());
+            printf("Autodecrement. DC: %f.\n",PWM.read());
         }
         wait_ms(500);
     }