Diff: Hexacopter/PING_rangefinder.h

Revision:

0:9b057566f9ee

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Hexacopter/PING_rangefinder.h	Mon Nov 01 20:39:01 2010 +0000
@@ -0,0 +1,203 @@
+#pragma once
+#ifndef PING_RANGEFINDER_H
+#define PING_RANGEFINDER_H
+
+#include <processes.h>
+#include <Mutexes.h>
+#include <channels.h>
+#define PINGPIN p22
+
+
+//DigitalOut led3(LED3); //these LEDs are used to indicate when an interrupt occurs.
+//DigitalOut led4(LED4);
+//byte count = 0;
+
+class rangefinder {
+public:
+    rangefinder()
+            :Pinterrupt(PINGPIN), PingPin(PINGPIN)
+     {
+            //led3 = ~(led4 = 0);
+            
+            time = 0;
+            enable_flag = false;
+            set_interrupts();
+            PingPin.mode(PullDown);
+            //Pinterrupt.mode(PullDown);
+    //        Pinterrupt.mode(PullUp);       
+            PingPin.output(); //set pingpin as output
+            PingPin = 0;
+    }
+
+    void ping() {
+        T.reset(); //reset the timer to 0
+        set_interrupts();
+        enable_flag = false;
+        PingPin.output(); //set as output
+        PingPin = 0; //output initiation sequence of 0 1 0 to the rangefinder
+        wait_us(2);
+        PingPin = 1;
+        wait_us(5);
+        PingPin = 0;
+        wait_us(1);
+        //printf("now waiting for input.\n");
+        PingPin.input(); //set as input
+        wait_us(10);
+        //set_interrupts();
+        enable_flag = true;
+        wait_ms(25); //more than required for maximum distance measurement
+        
+        
+        
+        //T.start(); //begin timing the length of time for an interrupt to occur
+    }
+    void set_interrupts()
+    {
+         Pinterrupt.fall(this, &rangefinder::set_time);
+         Pinterrupt.rise(this, &rangefinder::start_timing);
+    }
+    void disable_interrupts()
+    {
+         Pinterrupt.fall(NULL);
+         Pinterrupt.rise(NULL);
+    
+    } 
+    void start_timing() {  OS::TISRW ISRW;
+       if(enable_flag == true)
+       {
+           T.start();
+           //led3 = !led3;
+           //count++;       
+       }
+        
+        //printf("start_timing called.\n");
+    }
+
+    void set_time() { OS::TISRW ISRW;
+        if(enable_flag == true)
+        {
+            T.stop();
+            //led4 = !led4;
+            //disable_interrupts();
+            //enable_flag = false;
+            //printf("set_time being called...\n");
+            time = T.read_us();
+            //count++;
+        }
+                //printf("value stored in time %f: \n", time);
+        
+        //PingPin.output();
+        //PingPin = 0;
+        //printf("PING:%f\n",get_time());
+
+    }
+   
+
+
+    float get_time() {
+       //disable_interrupts();
+        return time/2.0;
+        
+    }
+
+   
+private:
+    Timer T;
+    float time; //time in us
+    InterruptIn Pinterrupt;
+    DigitalInOut PingPin;
+    bool enable_flag;
+    //Ticker TICKER;// send_ticker;
+    
+
+};
+
+
+
+
+
+
+
+
+
+
+extern BusOut leds;
+
+template<> OS_PROCESS void PING_PROC::Exec() //Output stream handling process
+{
+    byte M = 0;
+    rangefinder PING;
+ 
+
+char PIN_Return_chars[100]; //defined in accelerometer.h
+     
+     for(;;)
+     {
+       if(PING_MESSAGE.wait(80)) //length of time to wait also determines how rapidly to ticker ping
+       {    leds = 0x2;
+            M = PING_MESSAGE; //read the message that was destined for this process
+            PING_MESSAGE.reset();
+       
+           if(M == 0) //then ping! command was sent
+           {
+                {
+                    //OS::TISRW ISRW; //this is a critical section as timing is involved
+                    //this will not work though as it disables interrupts. 
+                    PING.ping();
+                }
+                
+                {   
+                    //TCritSect cs;
+                    sprintf(PIN_Return_chars, "PING:%f\n", PING.get_time()); //
+                 }
+                 //Ser_out_Mutex.Lock();
+                //if(TX_Channel.get_free_size() > strlen(Return_chars)+1)
+                    TX_channel.write(PIN_Return_chars, strlen(PIN_Return_chars)+1); //output the ping result
+                //Ser_out_Mutex.Unlock();
+                
+                
+           }
+       }
+       if(M == 1) //ticker ping
+       {
+            {
+                //OS::TISRW ISRW; //this is a critical section as timing is involved
+                PING.ping();
+            }
+            //Sleep(2);
+             {
+                //TCritSect cs;
+                sprintf(PIN_Return_chars, "PING:%f\n", PING.get_time()); //"PING:%f\n"
+              }
+              //Ser_out_Mutex.Lock();
+              //if(TX_Channel.get_free_size() > strlen(Return_chars)+1)
+               TX_channel.write(PIN_Return_chars, strlen(PIN_Return_chars)+1); //output the result
+              //Ser_out_Mutex.Unlock();
+             //TX_flag.Signal();
+            
+       }
+       
+              //PING_MESSAGE.reset();
+            
+        leds = 0x2;
+       
+     }
+}
+
+ 
+ #endif
+
+  //void enable_ticker() {
+    //    TICKER.attach_us(this, &rangefinder::ping, TX_RATE); //call ping() every 40 ms
+        //send_ticker.attach_us(this, &rangefinder::send_data, TX_RATE); //send the data out every 40 ms
+    //}
+    //void disable_ticker() {
+        //printf("ticker should now be detached.\n");
+    //    TICKER.detach();
+        //send_ticker.detach();
+    //}
+ 
+
+
+
+