main.cpp

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