Diff: main.cpp

Revision:

0:7a527a9bedce

Child:

1:7972095b7aea

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Sun Apr 21 12:39:43 2013 +0000
@@ -0,0 +1,108 @@
+#include "mbed.h"
+ 
+//are these actually used ???
+DigitalOut ext_led[8] = {p21,p22,p23,p24,p25,p26,p27,p28};
+//DigitalOut int_led[4] = {LED1, LED2, LED3, LED4};
+
+// from handbook for BusOut:  Flexible way to write multiple DigitalOut pins as one value
+BusOut int_led(LED1, LED2, LED3, LED4);  //four built-in LEDs used to display the counter from the trigger
+ 
+DigitalInOut fire(p20);     //connected to the tip of 2.5mm connector (T2i)
+DigitalInOut pre_fire(p19); //connected to the mid-connection for 2.5mm connector (T2i)
+
+InterruptIn x(p18); 
+Serial pc(USBTX, USBRX);
+
+
+#define US_INTERVAL 500
+    
+//set the resolution of the timing information
+#define MS_INTERVAL 2   //interval used to change the counter display 
+ 
+void resetLed()
+{
+    for(int i=0; i<8; i++)
+    {
+        ext_led[i] = 0;
+    }
+    int_led = 0;
+}
+
+//xFire procedure is not used in the logic in main 
+void xFire()
+{
+    for(int i=1; i<16; i++)
+    {
+        wait_us(US_INTERVAL);
+        int_led = i;
+    }
+    return;
+}
+
+volatile bool trigger = 0;
+Ticker trig;
+void setTrig()
+{
+    trigger = 1;
+}
+ 
+int main()
+{
+    // try open drain driving (internal pullup in camera?)
+    //x procedure not used below 
+    x.mode(PullUp);
+    x.fall(&xFire);   
+    
+    fire.output();  //set the fire pin as outoput
+    pre_fire.output();  //set the pre-fire pin as output
+    //fire.mode(OpenDrain);
+    
+    //set up for the first trigger
+    fire = 1;
+    pre_fire = 1;
+    
+    // reset the LED's
+    resetLed();
+    
+    //trig is a ticker used to repeatedly fire a trigger at the interval (e.g., 7.5 secs)
+    trig.attach(&setTrig, 7.5f);  //set ticker interval to 7.5secs
+    
+    // start the program
+    while(1)
+    {
+//        if(pc.readable())  //used to trigger from a keyboard click
+//        {
+//            char ch = pc.getc();  //read the keyboard click
+
+          //below used for repeatedly triggering on a ticker
+          if(trigger)  //is the ticker has fired the trigger, proceed ...
+          {
+            trigger = 0;  //reset the trigger to zero
+            
+            // turn all leds off to start the counter
+            resetLed();
+            
+            // pre-fire the trigger using the mid-body 2.5mm connection (T2i)
+            pre_fire = 0;
+            
+            wait(.25f);  //wait for 0.25 secs
+            
+            fire = 0; //fire the trigger using the tip connection
+            
+            wait(0.100f); // empirically known delay to get us to the range of the 4 timing LEDs 
+            
+            // maybe we need more or later just use these...
+            //just count up to 16 diaplaying the results on the LEDs
+            for(int i=1; i<16; i++)
+            {
+                wait_ms(MS_INTERVAL);
+                int_led = i;  //write to the BusOut to display the counter on 4 LEDs
+            }
+            
+            //reset for the next trigger
+            // release the trigger
+            fire = 1;
+            pre_fire = 1;
+        }
+    }
+}