Revision 0:e0ccf51d5ad5, committed 2017-04-27

Comitter:

rrutherford20

Date:

Thu Apr 27 16:48:15 2017 +0000

Commit message:

Final code + comments

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ExtendedTimer.lib	Thu Apr 27 16:48:15 2017 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/teams/Whitworth-EN173-Resources/code/ExtendedTimer/#7a6067de3bff

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SDFileSystem.lib	Thu Apr 27 16:48:15 2017 +0000
@@ -0,0 +1,1 @@
+https://developer.mbed.org/users/rrutherford20/code/SDFileSystem/#161fca56a12b

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Thu Apr 27 16:48:15 2017 +0000
@@ -0,0 +1,145 @@
+/*
+THIS CODE NEEDS TO BE PUT ONTO THE EMBED BEFORE LAUNCH FOR PROPER TSV DATA
+
+By Cameron Rutherford
+
+last updated: 4/27/2017
+
+Ozone detector code for near space research project
+
+This code collects data from the phototransistor with each LED on seperately,
+as well as reading the data when none of the LEDs are on in a TSV text file in the
+following format:
+
+Time (s)    Red light   Green light No light
+...         ...         ...         ...
+
+
+Green LEDs connected in parallel to pin 23
+Red LEDs connected in parallel to pin 22
+Phototransistor connected to pin 20
+SD card connected: MOSI - p5
+                   MISO - p6
+                   SCLK - p7
+                   CS - p8
+                   
+*/
+
+#include "mbed.h"
+#include "SDFileSystem.h"
+#include "ExtendedTimer.h" //Created by Dr Larkin to extend the timer object
+
+AnalogIn light(p20); //PhotoTransistor
+//Serial pc(USBTX,USBRX); this was used for debugging. uncomment this
+//                        and other pc.printf lines to debug/print to console
+SDFileSystem fs(p5, p6, p7, p8, "fs");
+ExtendedTimer t; //Used to keep track of the time
+Ticker sampleTime;
+DigitalOut doneLED(LED1); //used to indicate when the program has finished
+DigitalOut _2(LED2); //used to indicate if the mount was successful/unsuccessful
+DigitalOut _4(LED4); //used to indicate if the file open was successful/unsuccessful
+bool timeToRead;
+DigitalOut green(p23); //used to turn the two green/red LEDs on and off
+DigitalOut red(p22);
+FILE *data;
+void triggerCollection(); //used in the ticker to set timeToRead to true
+void SDcardDONE(); //unmount the SD card
+void take_reading(); //input data from the photransistor to the file
+void LED_OFF(); //used to check the LEDs are off and nothing went wrong - probably useless
+double collection_time = 24240; //time interval for collection to take place
+float collection_interval = 5 ; //time difference between each data point (red to green to none time)
+double num_averaged = 10000; //number of data points collected for each data reading
+                             //this aims to eliminate as much noise as possible
+float LED_on_time_delay = 1; //delay between each LED turning on and the data recording
+                             //used to make sure all remaining light from the LEDs is gone
+
+int main()
+{
+     // Mount the filesystem
+     bool mountFailure = fs.mount();
+     
+     if (mountFailure != 0) { //if failed to mount
+         //pc.printf("Failed to mount the SD card.\r\n");
+         _2 = 1;
+         wait(5);
+         return -1;
+     }
+    
+     data = fopen("/fs/data.txt","a");
+     
+     if (data == NULL) { //if failed to open the file
+         //pc.printf("Failed to open the file.\r\n");
+         fs.unmount();
+         _4 = 1;
+         wait(5);
+         return -1;
+     }
+    
+     // Write a header row
+     fprintf(data, "Time (s)\tRed light\tGreen light\tNo light\r\n");
+     //pc.printf("Time (s)\tRed light\tGreen light\tNo light\r\n");
+
+     // Start the timer and ticker
+     t.start();
+     sampleTime.attach(&triggerCollection, collection_interval); // write data every collection_interval seconds
+     timeToRead = true; // collect data at t = 0
+     while (t.read() < collection_time) {
+         if (timeToRead) {
+             timeToRead = false; // reset data collection flag
+             take_reading();
+             fclose(data); //make sure the data is written to the SD card to avoid data loss if power is cycled
+             data = fopen("/fs/data.txt","a");
+         }
+     }
+    
+     SDcardDONE();
+     return 0;
+}
+
+void take_reading() {
+    
+    float time = t.read(); //Get the current time
+    
+    double data_red = 0, data_green = 0, data_none = 0;
+    LED_OFF();
+    
+    red = 1; //Turn the red LEDs on and start recording data
+    wait(LED_on_time_delay);
+    for (double i = 0; i < num_averaged; i++) //average the data multiple times
+        data_red += light;
+    data_red = data_red / num_averaged;
+    
+    red = 0; //Turn the red LEDs off and the green LEDs on and start recording data
+    green = 1;
+    wait(LED_on_time_delay);
+    for (double i = 0; i < num_averaged; i++)
+        data_green += light;
+    data_green = data_green / num_averaged;
+    
+    green = 0; //Have all the LEDs off and record data
+    wait(LED_on_time_delay);
+    for (double i = 0; i < num_averaged; i++)
+        data_none += light;
+    data_none = data_none / num_averaged;
+    
+    fprintf(data,"%-.2f\t %-.8f\t %-15.8f\t %-15.8f \r\n", time, data_red, data_green, data_none); //The minus sign makes it left aligned (I think...)
+    //pc.printf("%-.2f\t %-.8f\t %-15.8f\t %-15.8f \r\n", time, data_red, data_green, data_none);
+}
+
+void triggerCollection() {
+    timeToRead = true; // flag to collect data
+}
+
+void SDcardDONE() {
+    // Close the file and unmount the file system so the SD card is happy
+     fclose(data);
+     fs.unmount();
+     // Turn on LED to let user know it is safe to remove the SD card
+     doneLED = 1;
+}
+
+void LED_OFF() {
+    green = 0;
+    red = 0;
+    doneLED = 0;
+}
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed.bld	Thu Apr 27 16:48:15 2017 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/mbed_official/code/mbed/builds/e1686b8d5b90
\ No newline at end of file