Diff: main.cpp

Revision:

0:a618e508f7e5

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Sun Jun 16 15:41:23 2013 +0000
@@ -0,0 +1,47 @@
+/* Program Example 14.3: Uses digital input and output using control registers, and flashes an LED. LEDS connect to mbed pins 25 and 26. Switch input to pin 9.
+                                          */
+// function prototypes                                   
+void delay(void);
+//Define Digital I/O registers
+#define FIO0DIR0 (*( volatile unsigned char *)(0x2009C000))
+#define FIO0PIN0 (*( volatile unsigned char *)(0x2009C014))
+#define FIO2DIR0 (*(volatile unsigned char *)(0x2009C040)) 
+#define FIO2PIN0 (*(volatile unsigned char *)(0x2009C054))
+//some variables
+char a;
+char b;
+char i;
+
+int main() {
+   FIO0DIR0=0x00;             // set all bits of port 0 byte 0 to input 
+   FIO2DIR0=0xFF;             // set port 2 byte 0 to output
+   while(1) {
+     if (FIO0PIN0&0x01==1){   // bit test port 0 pin 0 (mbed pin 9)
+       a=0x01;                // this reverses the order of LED flashing
+       b=0x02;                // based on the switch position
+     } 
+     else {    
+       a=0x02;
+       b=0x01;
+     }
+     FIO2PIN0 |= a;        
+     delay();
+     FIO2PIN0 &= ~a;                    
+     delay();
+             
+     for (i=1;i<=3;i++){
+       FIO2PIN0 |= b;    
+       delay();
+       FIO2PIN0 &= ~b;             
+       delay();
+     }
+   }                          //end while loop
+}
+
+void delay(void){            //delay function.
+    int j;                      //loop variable j
+    for (j=0; j<1000000; j++) {
+        j++;
+        j--;                      //waste time
+    }
+}