Changed PWM_Module #2 and the Function of the Propulsion Engine Direc…

…tional Stepper Motor

Changed the PWM_Module 2 to use Timer1's prescaler of 64 to allow for smaller frequency PWM signals.

Updated the main driver such that the number of pulses sent to the stepper motor has a 1:1 relationship to the number of steps taken by the motor.  The base configuration is currently a PWM of 400Hz coupled with a 30 RPM max speed on the stepper motor, with each PWM pulse moving the stepper by +/-1 count.

Dependencies/PWM Generation/PWM.c

@@ -161,9 +161,19 @@ void PWM_OC2_Initialize(PWM_Module* OC2_PWM_module)
     OC2_PWM_module->UpdateFrequency(OC2_PWM_module);
     OC2_PWM_module->UpdateDutyCycle(OC2_PWM_module);
 
+    //turns timer1 off to configure it
+    T1CON = 0b0000000000000000;
+    //sets a 1:64 input clock prescaler, which increments the timer every
+    //8th clock cycle (from Fcy by default)
+    T1CONbits.TCKPS = 0b10;
+    //sets this timer's clock source to Fcy
+    T1CONbits.TCS = 0b0;
+    //turns timer1 back on after it is configured
+    T1CONbits.TON = 1;
+
     OC2CON2 = 0b00011111;
 
-    OC2CON1bits.OCTSEL = 0b111;
+    OC2CON1bits.OCTSEL = 0b100;
 
     OC2CON1bits.OCM = 0b110;
 }
@@ -188,7 +198,7 @@ void PWM_Update_OC2_DutyCycle(const PWM_Module* OC2_PWM_module)
 
 void PWM_Update_OC2_Frequency(const PWM_Module* OC2_PWM_module)
 {    
-    double totalClockCycles = (double)1.0 / (OC2_PWM_module->frequency * TCY) - 1;
+    double totalClockCycles = (double)1.0 / (OC2_PWM_module->frequency * TCY * TIMER_PRESCALER) - 1;
     OC2RS = (int)totalClockCycles;
 
     OC2_PWM_module->UpdateDutyCycle(OC2_PWM_module);

Finalized Design/Final Project/main_driver.c

@@ -30,7 +30,7 @@
 
 //this dead zone will be used to prevent the user from turning the propulsion motor without intentionally
 //moving the left joystick to the left or right.
-#define DEAD_ZONE_OFFSET 0.1
+#define DEAD_ZONE_OFFSET 0.5
 
 //basic initialization for all pins
 void PIC_Initialization(void)
@@ -112,7 +112,7 @@ int main(void)
     propulsion_throttle_servo_output.frequency = 50;
     propulsion_throttle_servo_output.UpdateFrequency(&propulsion_throttle_servo_output);
 
-    turn_propulsion_engine_output.frequency = 20000;
+    turn_propulsion_engine_output.frequency = 400;
     turn_propulsion_engine_output.UpdateFrequency(&turn_propulsion_engine_output);
 
     while(true)
@@ -155,41 +155,33 @@ int main(void)
         }
 
 		//represents a leftward turn of the propulsion engine
+        //at the moment, the frequency of the PWM signal * the number of counts per trigger = 800 (counts per rotation) * rotations per second
+        //this will allow for smooth movement of the stepper motor
+        //if PWM frequency * counts per trigger > 800 * RPS, then the user input will experience a delay in controlling the stepper motor
+        //if PWM frequency * counts per trigger < 800 * RPS, then the user input will cause jerking in the stepper motor response
         if (propulsion_direction_motor_input.dutyCyclePercentage < MIDPOINT_INPUT_SIGNAL_DUTY_CYCLE - DEAD_ZONE_OFFSET)
         {
 			//This is the enable bit for the stepper motor responsible for turning the propulsion engine to control direction
-            LATAbits.LATA2 = 1;
-			//this is the bit to control the direction of rotation of the stepper motor (CW or CCW)
-			//when the signal is high, the motor shaft rotates CCW, which makes the craft rotate to the left
-			LATAbits.LATA3 = 1;
+            LATAbits.LATA2 = 0;
 
-            turn_propulsion_engine_output.dutyCyclePercentage = 50;
-            turn_propulsion_engine_output.UpdateDutyCycle(&turn_propulsion_engine_output);
-            __delay_us(100);
-            turn_propulsion_engine_output.dutyCyclePercentage = 0;
+            turn_propulsion_engine_output.dutyCyclePercentage = 5;
             turn_propulsion_engine_output.UpdateDutyCycle(&turn_propulsion_engine_output);
         }
         //represents a rightward turn of the propulsion engine
         else if (propulsion_direction_motor_input.dutyCyclePercentage >= MIDPOINT_INPUT_SIGNAL_DUTY_CYCLE + DEAD_ZONE_OFFSET)
         {
             //This is the enable bit for the stepper motor responsible for turning the propulsion engine to control direction
             LATAbits.LATA2 = 1;
-			//this is the bit to control the direction of rotation of the stepper motor (CW or CCW)
-			//when the signal is low, the motor shaft rotates CW, which makes the craft rotate to the right
-			LATAbits.LATA3 = 0;
 
-            turn_propulsion_engine_output.dutyCyclePercentage = 50;
-            turn_propulsion_engine_output.UpdateDutyCycle(&turn_propulsion_engine_output);
-            __delay_us(100);
-            turn_propulsion_engine_output.dutyCyclePercentage = 0;
+            turn_propulsion_engine_output.dutyCyclePercentage = 5;
             turn_propulsion_engine_output.UpdateDutyCycle(&turn_propulsion_engine_output);
         }
         //the motor holds its position
         else
         {
-            LATAbits.LATA2 = 1;
-            LATAbits.LATA3 = 0;
-            turn_propulsion_engine_output.dutyCyclePercentage = 0;
+            LATAbits.LATA2 = 0;
+
+            turn_propulsion_engine_output.dutyCyclePercentage = 100;
             turn_propulsion_engine_output.UpdateDutyCycle(&turn_propulsion_engine_output);
         }
     }