Diff: Tasks.cpp

Revision:

10:c0531edf4850

Parent:

9:46408a8dea0c

--- a/Tasks.cpp	Wed Mar 02 09:38:47 2016 +0000
+++ b/Tasks.cpp	Wed Mar 02 13:38:27 2016 +0000
@@ -9,17 +9,9 @@
  
  Date:              February 2016
  
- Function:          This 
- 
- Version:           1.0
- 
- Version History
- ---------------
- 
- 1.1                rgdfgdfgdfggdfgdg
- 
- 1.0                gdgddfdddgd
-    
+ Function:          This code defines the operations of all of the 
+                    methods, or tasks used by the cyclic executive
+     
  ##################################################################### */
 
 #include "mbed.h"
@@ -28,37 +20,81 @@
 /* ==================================== Task 1 ==================================== */
 Task1::Task1(PinName squareWaveInPin)
 {
+    // Construct new DigitalIn object using the pin number provided
     _squareWaveIn = new DigitalIn(squareWaveInPin);
 }
     
 void Task1::MeasureFrequency()
 {
-    _Task1Timer.start();
-    _squareWaveIn -> rise(this,&Task1::StopCounter);    
-}
-
-void Task1::StopCounter()
-{
+    // If pulse is initially low, wait until rising edge before starting timer    
+    if(_squareWaveIn -> read() == LOW)
+    {
+        while(_squareWaveIn -> read() == LOW)
+        {
+            wait_us(SAMPLE_FREQ);
+        }
+        
+        _Task1Timer.start();
+        
+        // Once timer has started, wait until falling edge before breaking and
+        // stopping timer
+        while(_squareWaveIn -> read() == HIGH)
+        {
+            wait_us(SAMPLE_FREQ);
+        }
+    }
+    
+    // If pulse is initially high, wait until falling edge before starting timer
+    else if(_squareWaveIn -> read()== HIGH)
+    {
+        while(_squareWaveIn -> read() == HIGH)
+        {
+            wait_us(SAMPLE_FREQ);
+        }
+        
+        _Task1Timer.start();
+        
+        // Once timer has started, wait until rising edge before breaking and
+        // stopping timer
+        while(_squareWaveIn -> read() == LOW)
+        {
+            wait_us(SAMPLE_FREQ);
+        }
+    }
+    
+    // Stop timer after breaking while loop conditions    
     _Task1Timer.stop();
-    measuredFrequency = _Task1Timer.read_us();
+    
+    // Calculate frequency from timer (either high or low time)
+    // do this by multiplying the time by 2 (high + low time) and dividing it,
+    // converting it to a frequency
+    // Store frequency in private class field
+    Task1::measuredFrequency = (1000000/(2*_Task1Timer.read_us()));
+    
+    // Reset timer
     _Task1Timer.reset();
+  
 }
 
 int Task1::ReadFrequency()
 {
-    _squareWaveIn -> rise(this,&Task1::MeasureFrequency);
+    // Run private method to calculate the frequency
+    MeasureFrequency();   
     
+    // Return private field showing the newest frequency calculation
     return measuredFrequency;
 }
 
 /* ==================================== Task 2 ==================================== */
 Task2::Task2(PinName digitalInCheckPin)
 {
+    //Construct new DigitalIn object from provided pin
     _digitalInCheck = new DigitalIn(digitalInCheckPin);
 }
 
 bool Task2::digitalInState()
 {
+    // Check state of pin, returning a TRUE if high, false if LOW
     if(_digitalInCheck -> read())
     {
         return TRUE;
@@ -73,11 +109,13 @@
 /* ==================================== Task 3 ==================================== */
 Task3::Task3(PinName WatchdogPin)
 {
+    // Construct new DigitalOut object using provided pin
     _Watchdog = new DigitalOut(WatchdogPin);
 }
     
 void Task3::OutputWatchdogPulse()
 {
+    // Produce a 15ms pulse when method called
     _Watchdog -> write(HIGH);
     wait_ms(WATCHDOG_PULSE_WIDTH);
     _Watchdog -> write(LOW);
@@ -87,41 +125,44 @@
 /* ==================================== Task 4 ==================================== */
 Task4::Task4(PinName Analog1Pin,PinName Analog2Pin)
 {
+    // Construct new AnalogIn objects from provided pins
     _AnalogIn1 = new AnalogIn(Analog1Pin);
     _AnalogIn2 = new AnalogIn(Analog2Pin);
 }
 
 float *Task4::returnAnalogReadings()
 {
+    // Declare local scope fields to retain current totals
     float readBuffer_1 = 0.0;
     float readBuffer_2 = 0.0;
-    
-    float outputBuffer[2];
-       
-//    outputBuffer[0] = _AnalogIn1 -> read();
-//    outputBuffer[1] = _AnalogIn2 -> read();
 
+    // Read 4 samples from AnalogIn pins
     for(int readCount = 0;readCount < NUM_ANALOG_SAMPLES; readCount++)
     {
-        readBuffer_1 += ((_AnalogIn1 -> read())*3.3);
-//        printf("Buffer 1 %f\r\n",readBuffer_1);
-        readBuffer_2 += ((_AnalogIn2 -> read())*3.3); 
-//        printf("Buffer 2 %f\r\n",readBuffer_2); 
+        // Add to readBuffer with new weighted reading.
+        // 3.3v due to supply voltage
+        readBuffer_1 += ((_AnalogIn1 -> read())*V_SUPPLY);
+        readBuffer_2 += ((_AnalogIn2 -> read())*V_SUPPLY); 
     }
     
+    // Construct local buffer
+    float outputBuffer[2];
+    
+    // Construct elements in outputBuffer array as averaged sample
     outputBuffer[0] = readBuffer_1/NUM_ANALOG_SAMPLES;
-//    printf("outputBuffer[0] %f\r\n",outputBuffer[0]);
     outputBuffer[1] = readBuffer_2/NUM_ANALOG_SAMPLES;
-//    printf("outputBuffer[1] %f\r\n",outputBuffer[1]);
     
+    // Construct pointer to return the initial element of the outputBuffer
     float *outputBufferPtr =&outputBuffer[0];
-        
+    
+    // Return pointer to first element of outputBuffer
     return outputBufferPtr;    
 }
 
 /* ==================================== Task 5 ==================================== */
 Task5::Task5(PinName sda, PinName scl, int address)
 {
+    // Declare and initialise the LCD display
     _par_port = new MCP23017(sda,scl,address);
     _lcd = new WattBob_TextLCD(_par_port);
     _par_port -> write_bit(1,BL_BIT);
@@ -133,6 +174,7 @@
                             float task4Channel1,
                             float task4Channel2  )
 {
+    // Print standard expression using input fields
     _lcd -> cls();
     _lcd -> locate(0,0);
     _lcd -> printf("F-%4dHz S1-%d E%d",task1Param,task2Param,errorState);
@@ -143,10 +185,16 @@
 /* ==================================== Task 6 ==================================== */
 int Task6::updateErrorCode(int switch_1, float analog1, float analog2)
 {
-    if(switch_1 == 1 && (analog1 > analog2))
-    return ERROR_CODE_CDTN_MET;
+    // Using input fields, conduct a logical equation7
+    // returning CDTN_MET when true, CDTN_FAIL when false
+    if(switch_1 == HIGH && (analog1 > analog2))
+    {
+        return ERROR_CODE_CDTN_MET;
+    }
     else
-    return ERROR_CODE_CDTN_FAIL;
+    {
+        return ERROR_CODE_CDTN_FAIL;
+    }
 }
 
 /* ==================================== Task 5 ==================================== */
@@ -157,19 +205,26 @@
                 const char *SDName,
                 const char *dir    )
 {
+    // Construct new SDFileSystem object
     _sd = new SDFileSystem(mosi,miso,sck,cs, SDName);
+    
+    // Call private method to create default directory
     makeDirectory(dir);
 }
 
 void Task7::makeDirectory(const char *dir)
 {
+    // Create directory onto sd card
     mkdir(dir,0777);
 }
 
 int Task7::openFile(const char *dirFile,const char *accessType)
 {
-    fp = fopen(dirFile,accessType);
-    if(fp == NULL)
+    // Create pointer to FILE object
+    Task7::fp = fopen(dirFile,accessType);
+    
+    // If failed to open file, return 1, indicating error, else return 0
+    if(Task7::fp == NULL)
     {
         return 1;
     }
@@ -178,10 +233,12 @@
 
 void Task7::writeData(const char *dataStream)
 {
-    fprintf(fp,dataStream);
+    // Print Stream of data to FILE object fp
+    fprintf(Task7::fp,dataStream);
 }
 
 void Task7::closeFile()
 {
-    fclose(fp);    
+    // Close file located at fp
+    fclose(Task7::fp);    
 }
\ No newline at end of file