Diff: main.cpp

Revision:

0:b44ffe9b1e5b

diff -r 000000000000 -r b44ffe9b1e5b main.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Thu Jul 29 11:56:42 2010 +0000
@@ -0,0 +1,194 @@
+/******************************************************************************
+¬   Knightrider.c                                                             ¬
+¬   Uses the onboard LEDS on mBED to continuously perform LED chaser sequence ¬
+¬   LED Chaser sequence timimg can be changed by using the serial comms and   ¬
+¬   activity on digital port.                                                 ¬
+¬                                                                             ¬
+¬   Written by RandomSingh. 05/2010                                           ¬
+¬                                                                             ¬
+******************************************************************************/
+
+/* Libraries */
+#include "mbed.h"
+
+/* Output Assignements */
+DigitalOut myled(LED1);
+DigitalOut myled2(LED2);
+DigitalOut myled3(LED3);
+DigitalOut myled4(LED4);
+
+/* Input Assignments */
+DigitalIn enable(p5);
+
+/* Interrupt Assignemnts */
+InterruptIn event(USBRX);
+InterruptIn event2(p16);
+
+/* Serial Port Assignment */
+Serial pc(USBTX, USBRX); // tx, rx
+
+
+/* Macro Definitions */
+#define LONGER 0.9
+#define LONG 0.4
+#define SHORT 0.05
+#define FWD 0
+#define REV 1
+#define SLOW 0
+#define MEDIUM 1
+#define FAST 2
+#define ON 1
+#define OFF 0
+
+/* Prototype Function declartions */
+void initialise_LEDS();
+void trigger();
+void LED_chaser_sequence();
+
+/* External Variables */
+int timer;
+short speed;
+int direction = FWD;
+int phase;
+
+
+
+int main() {
+
+    event.rise(&trigger);           // Set up interrupts
+    event2.rise(&trigger);
+    initialise_LEDS();
+    pc.printf("Speed is slow\r\n"); // Default speed is slow
+    
+    while(1) 
+    {// Start of while
+    
+        LED_chaser_sequence();
+    
+    }// End of while
+}// End of main
+
+
+/******************************************************************************
+¬   trigger function - ISR                                                    ¬
+¬   If activity on the rx line of the serial port then this ISR executes      ¬
+¬   This ISR changes the external variable 'speed' value, which is used for   ¬
+¬   timing of the sequence.                                                   ¬
+¬                                                                             ¬
+¬   The objective of this ISR is to change the 'speed' value & transmit a     ¬
+¬   a message to the serial port.                                             ¬                                                                         
+¬                                                                             ¬
+******************************************************************************/
+void trigger()
+{// Start of trigger
+        if(speed > FAST)                       // This bit of the code limits value of speed to 2
+        {// Start of if                        // as there are only three levels of timing 
+         speed = SLOW;
+         pc.printf("Speed is slow\r\n");
+        }// End of if
+        else
+        {// Start of else
+         speed++;
+        }// End of else
+    
+    if(speed == MEDIUM)
+        pc.printf("Speed is medium\r\n");
+    
+    if(speed == FAST)
+        pc.printf("Speed is fast\r\n");
+
+}// End of trigger
+
+void LED_chaser_sequence()
+{// Start of LED_chaser_sequence
+switch(phase)
+    {// Start of switch
+    case 0:  myled = OFF;
+             myled2 = OFF;
+             myled3 = OFF;
+             myled4 = OFF;
+             wait(LONG);
+             wait(SHORT);
+             direction = FWD;
+             phase++;
+             break;
+    case 1:  myled = ON;
+             myled2 = OFF;
+             myled3 = OFF;
+             myled4 = OFF;
+             wait(SHORT);
+             if(direction == FWD)
+             {// Start of if
+                phase++;
+             }// End of if
+             else
+             {// Start of else
+                phase--;
+             }// End of else
+             break;
+    case 2:  myled = OFF;
+             myled2 = ON;
+             myled3 = OFF;
+             myled4 = OFF;
+             wait(SHORT);
+                if(direction == FWD)
+             {// Start of if
+                phase++;
+             }// End of if
+             else
+             {// Start of else
+                phase--;
+             }// End of else
+             break;
+    case 3:  myled = OFF;
+             myled2 = OFF;
+             myled3 = ON;
+             myled4 = OFF;
+             wait(SHORT);
+                if(direction == FWD)
+             {// Start of if
+                phase++;
+             }// End of if
+             else
+             {// Start of else
+                phase--;
+             }// End of else
+             break;
+   case  4:  myled = OFF;
+             myled2 = OFF;
+             myled3 = OFF;
+             myled4 = ON;
+             wait(SHORT);
+             direction = REV;
+             phase--;
+             break;
+   default : 
+            wait(SHORT);
+            break;
+            
+    }// End of switch
+    
+    switch(speed)
+    {// Start of switch
+        case SLOW   : wait(LONGER);
+                      break;
+        case MEDIUM : wait(LONG);
+                      break;
+        case FAST   : wait(SHORT);
+                      break;
+        default     :
+                      wait(SHORT);
+                      break;
+    }// End of switch
+
+}// End of LED_chaser_sequence
+
+void initialise_LEDS()
+{// Start of initialise_LEDS
+
+    myled = OFF;
+    myled2 = OFF;
+    myled3 = OFF;
+    myled4 = OFF;
+
+}// End of initialise_LEDS
\ No newline at end of file