main.cpp

00001 #include "mbed.h"
00002 #include "rtos.h"
00003 #include "string.h"
00004 #include <stdio.h>
00005 #include <ctype.h>
00006 
00007 #define SWITCH1_RELEASE 1
00008 
00009 void thread1();
00010 void thread2();
00011 void switchISR();
00012 
00013 //Analogue inputs
00014 AnalogIn adcIn(A0);
00015 
00016 //Digital outputs
00017 DigitalOut onBoardLED(LED1);
00018 DigitalOut redLED(D7);
00019 DigitalOut yellowLED(D6);
00020 DigitalOut greenLED(D5);
00021 
00022 //Digital inputs
00023 DigitalIn  onBoardSwitch(USER_BUTTON);
00024 DigitalIn  sw1(D4);                         //CONSIDER CHANGING THIS TO AN INTERRUPT
00025 DigitalIn  sw2(D3);
00026 
00027 //Threads
00028 Thread *t1;
00029 
00030 //Class type
00031 class message_t {
00032 public:    
00033     float    adcValue;    
00034     int sw1State;
00035     int sw2State;
00036     
00037     //Constructor
00038     message_t(float f, int s1, int s2) {
00039         adcValue = f;
00040         sw1State = s1;
00041         sw2State = s2;    
00042     }
00043 };
00044  
00045 //Memory Pool - with capacity for 16 message_t types
00046 MemoryPool<message_t, 16> mpool;
00047 
00048 //Message queue - matched to the memory pool
00049 Queue<message_t, 16> queue;
00050 
00051 // Call this on precise intervals
00052 void adcISR() {
00053     
00054     //Read sample - make a copy
00055     float sample = adcIn;
00056     //Grab switch state
00057     uint32_t switch1State = sw1;
00058     uint32_t switch2State = sw2;
00059     
00060     //Allocate a block from the memory pool
00061     message_t *message = mpool.alloc();
00062     if (message == NULL) {
00063         //Out of memory
00064         redLED = 1;
00065         return;   
00066     }
00067     
00068     //Fill in the data
00069     message->adcValue = sample;
00070     message->sw1State = switch1State;
00071     message->sw2State = switch2State;
00072     
00073     //Write to queue
00074     osStatus stat = queue.put(message);    //Note we are sending the "pointer"
00075     
00076     //Check if succesful
00077     if (stat == osErrorResource) {
00078         redLED = 1; 
00079         printf("queue->put() Error code: %4Xh, Resource not available\r\n", stat);   
00080         mpool.free(message);
00081         return;
00082     }
00083 }
00084 
00085 //Normal priority thread (consumer)
00086 void thread1() 
00087 {      
00088     while (true) {
00089         //Block on the queue
00090         osEvent evt = queue.get();
00091         
00092         //Check status
00093         if (evt.status == osEventMessage) {
00094             message_t *pMessage = (message_t*)evt.value.p;  //This is the pointer (address)
00095             //Make a copy
00096             message_t msg(pMessage->adcValue, pMessage->sw1State, pMessage->sw2State);
00097             //We are done with this, so give back the memory to the pool
00098             mpool.free(pMessage);
00099             
00100             //Echo to the terminal
00101             printf("ADC Value: %.2f\t",    msg.adcValue);
00102             printf("SW1: %u\t",             msg.sw1State);
00103             printf("SW2: %u\n\r",             msg.sw2State);
00104         }
00105 
00106              
00107     } //end while
00108 }
00109 
00110 
00111 // Main thread
00112 int main() {
00113     redLED    = 0;
00114     yellowLED = 0;
00115     greenLED  = 0;
00116            
00117     //Start message
00118     printf("Welcome\n");           
00119    
00120     //Hook up timer interrupt   
00121     Ticker timer; 
00122     timer.attach(&adcISR, 0.1);
00123                
00124     //Threads
00125     t1 = new Thread();
00126     t1->start(thread1); 
00127     
00128     printf("Main Thread\n");
00129     while (true) {
00130         Thread::wait(5000);
00131         puts("Main Thread Alive");
00132     }
00133 }
00134 
00135