MSP430 practice for web developer

    There are plenty of articles for beginners on the hub - how magical and wonderful this Texas Instruments MSP430 LaunchPad is. However, usually no one goes beyond the standard flasher with an LED. It’s time to correct this situation.
    As a team, we use the good old SVN for version control. It would seem, where does the microcontrollers?
    Just to signal the next commit to the repository, I adapted this marvelous contraption.



    Idea

    I would like a device that will signal a melody about the next commit to any of our repositories. It would be nice for each developer to have their own unique melody, and everyone would hear who just made the next commit.

    Project

    As a web frontend, WebSVN is closed to SVN, closed by Basic authorization. This way we can access the list of projects and their revisions. In turn, we need a process that, according to a schedule, for example, once a minute will check project repositories for a new commit. Since PHP was closest to hands, it was decided to write on it. The working system is Windows 7 with Apache 2.1 + PHP 5.3.6.
    When a new commit is detected, the script sends a control command to the device on the COM port stating that the author’s melody should be played.

    So, we have WebSVN: Using



    PHP, we parse the list of projects and look at each project:
    index.php
    loadHTML($page);
    $links = $doc->getElementsByTagName('a');
    foreach ($links as $link) {
    	$link = dom2array($link);
    	if (strpos($link['@attributes']['href'], 'listing.php?repname') !== false) {
    		$projectName = $link['#text'];
    		checkSVNCommit($projectName);
    	}
    }
    

    In order to log in through Basic Auth, we use the functions of the CURL library.
    We also use DOMDocument and DOM to parse HTML.

    Because working with the DOM from PHP is pretty tedious, but we just need to take all the links, use the dom2array () function:
    functions.php dom2array ()
    /**
     * Парсит DOM узел в массив
     * @param object $node узел
     */
    function dom2array($node) {
      $res = array();
      if($node->nodeType == XML_TEXT_NODE){
          $res = $node->nodeValue;
      }
      else{
          if($node->hasAttributes()){
              $attributes = $node->attributes;
              if(!is_null($attributes)){
                  $res['@attributes'] = array();
                  foreach ($attributes as $index=>$attr) {
                      $res['@attributes'][$attr->name] = $attr->value;
                  }
              }
          }
          if($node->hasChildNodes()){
              $children = $node->childNodes;
              for($i=0;$i<$children->length;$i++){
                  $child = $children->item($i);
                  $res[$child->nodeName] = dom2array($child);
              }
          }
      }
      return $res;
    }
    


    Each project has its own page, which indicates the latest revision and its author.



    Using all the same CURL, we pick out the revision number and its author. Parsing through explode () and strpos () is terrible, but will whip up.
    functions.php checkSVNCommit ()
    /**
     * Проверяем ревизию и вызываем бибикало, если что
     * @param string $projectName название проекта
     */
    function checkSVNCommit($projectName) {
    	require 'config.php'; // Конфиг у нас тут подключается локально
      $old_rev = @file_get_contents('revisions/'.$projectName.'.txt');
    	$rev = 0;
    	$user = 'unknown';
    	// Готовим CURL
    	$s = curl_init();
    	curl_setopt($s, CURLOPT_URL, $svnURL.'/listing.php?repname='.urlencode($projectName).'&path=%2F&sc=0'); 
    	curl_setopt($s, CURLOPT_USERPWD, $authLogin.':'.$authPass);
    	curl_setopt($s, CURLOPT_USERAGENT, 'CommitBeep 1.0');
    	curl_setopt($s, CURLOPT_REFERER, $svnURL);
    	curl_setopt($s, CURLOPT_RETURNTRANSFER, true);
    	// Получаем список проектов
    	$page = curl_exec($s);
    	$httpCode = curl_getinfo($s, CURLINFO_HTTP_CODE);
    	curl_close($s);
    	// Весьма топорная реализация, но зато наглядно и быстро
    	$page = explode("\n", strip_tags($page));
    	foreach($page as $line) {
    		if (strpos($line, 'Last modification:') !== false) {
    			$line = explode(' ', $line);
    			$rev = $line[3];
    			$user = $line[5];
    		}
    	}
    	echo "$projectName $rev $user
    \n"; // Ревизия поменялась? Бибикаем! if ($rev != $old_rev) { beep($comNumber, getMelodyByUser($user)); file_put_contents('revisions/'.$projectName.'.txt', $rev); } }


    The implementation is banal and clumsy in places, but it works great. We read the old revision from the text file and compare it with the current one. If they differ, write and beep.

    First pitfalls

    I was 146% sure that working with COM ports is not difficult. As it turned out, the old fopen method (“COM6:”, “w +”) on Windows 7 no longer works. There are not enough access rights. In addition, even if the console redirects the output to the port, an access error will occur again. So from cmd (bat) - files we won’t succeed either, and through exec () it won’t work either.
    Strong google brought me to the Windows extension - PHP Serial.
    It connects like all extensions, quite simply and works like two fingers:
    functions.php beep ()
    /**
     * Посылает сигнал бибикалу
     * @param integer $com номер COM-порта
     * @param integer $melody номер мелодии
     */
    function beep($com = 6, $melody = 1) {
    	ser_open("COM".$com, 9600, 8, "None", "1", "None");
    	ser_write("$melody");
    	ser_close();
    }
    


    Bibikalo with a microcontroller

    It is the turn to program LaunchPad. Take Energia as your development environment.
    Unlike Arduino, for MSP430 it is not so obvious how to work with Serial port. It turns out that the TimerSerial library coexists, which is a modification of the Arduino-based Serial base library.
    A little effort, and you can write and read in the terminal.
    An example of working with the terminal
    #include 
    TimerSerial mySerial;
    // Начальные установки
    void setup() {
      mySerial.begin();
      mySerial.println("Welcome to CommitBeep 1.0");  
    }
    // Главный цикл
    void loop() {
      while (mySerial.available()) {
        char inChar = (char)mySerial.read(); 
        mySerial.write(inChar);
        delay(100);
      }
    }
    


    This simple little program reads a character and immediately writes it back. Like an echo.

    Underwater rocks. To be continued.

    So, with the reception and transmission of data sorted out. Now the beep.
    The standard Tone library is also somehow modified in Energia. And the most unpleasant, they are not friends with TimerSerial in any way. Probably used common timers or something else like that, but together they could not be used.
    I had to write my bike.

    Tame bibikalo
    #define NOTE_G3  196
    #define NOTE_A3  220
    #define NOTE_C4  262
    int speakerPin;
    // Начальные установки
    void setup() {
      speakerPin = 14; // контакт 1.6 (или 14) у нас подключён к бибикалу
      pinMode(speakerPin, OUTPUT);
      beep();
    }
    void playTone(int tone, int duration) {
      for (long i = 0; i < duration * 1000L; i += tone * 2) {
        digitalWrite(speakerPin, HIGH);
        delayMicroseconds(tone);
        digitalWrite(speakerPin, LOW);
        delayMicroseconds(tone);
      }
      digitalWrite(speakerPin, LOW);
    }
    // Бибикало
    void beep() {
      int melody[] = {NOTE_C4, NOTE_G3, NOTE_G3, NOTE_A3, NOTE_G3};
      int noteDurations[] = {4,8,8,4,4};
      for (int thisNote = 0; thisNote < 4; thisNote++) {
        int noteDuration = 1000/noteDurations[thisNote];
        playTone(melody[thisNote], noteDuration);
      }
    }
    


    All troubles are solved, it remains to write the code. In general, the rest is quite simple.
    Combine and get our sketch:
    commit_beep.ino
    #include 
    #define NOTE_B0  31
    #define NOTE_C1  33
    #define NOTE_CS1 35
    #define NOTE_D1  37
    #define NOTE_DS1 39
    #define NOTE_E1  41
    #define NOTE_F1  44
    #define NOTE_FS1 46
    #define NOTE_G1  49
    #define NOTE_GS1 52
    #define NOTE_A1  55
    #define NOTE_AS1 58
    #define NOTE_B1  62
    #define NOTE_C2  65
    #define NOTE_CS2 69
    #define NOTE_D2  73
    #define NOTE_DS2 78
    #define NOTE_E2  82
    #define NOTE_F2  87
    #define NOTE_FS2 93
    #define NOTE_G2  98
    #define NOTE_GS2 104
    #define NOTE_A2  110
    #define NOTE_AS2 117
    #define NOTE_B2  123
    #define NOTE_C3  131
    #define NOTE_CS3 139
    #define NOTE_D3  147
    #define NOTE_DS3 156
    #define NOTE_E3  165
    #define NOTE_F3  175
    #define NOTE_FS3 185
    #define NOTE_G3  196
    #define NOTE_GS3 208
    #define NOTE_A3  220
    #define NOTE_AS3 233
    #define NOTE_B3  247
    #define NOTE_C4  262
    #define NOTE_CS4 277
    #define NOTE_D4  294
    #define NOTE_DS4 311
    #define NOTE_E4  330
    #define NOTE_F4  349
    #define NOTE_FS4 370
    #define NOTE_G4  392
    #define NOTE_GS4 415
    #define NOTE_A4  440
    #define NOTE_AS4 466
    #define NOTE_B4  494
    #define NOTE_C5  523
    #define NOTE_CS5 554
    #define NOTE_D5  587
    #define NOTE_DS5 622
    #define NOTE_E5  659
    #define NOTE_F5  698
    #define NOTE_FS5 740
    #define NOTE_G5  784
    #define NOTE_GS5 831
    #define NOTE_A5  880
    #define NOTE_AS5 932
    #define NOTE_B5  988
    #define NOTE_C6  1047
    #define NOTE_CS6 1109
    #define NOTE_D6  1175
    #define NOTE_DS6 1245
    #define NOTE_E6  1319
    #define NOTE_F6  1397
    #define NOTE_FS6 1480
    #define NOTE_G6  1568
    #define NOTE_GS6 1661
    #define NOTE_A6  1760
    #define NOTE_AS6 1865
    #define NOTE_B6  1976
    #define NOTE_C7  2093
    #define NOTE_CS7 2217
    #define NOTE_D7  2349
    #define NOTE_DS7 2489
    #define NOTE_E7  2637
    #define NOTE_F7  2794
    #define NOTE_FS7 2960
    #define NOTE_G7  3136
    #define NOTE_GS7 3322
    #define NOTE_A7  3520
    #define NOTE_AS7 3729
    #define NOTE_B7  3951
    #define NOTE_C8  4186
    #define NOTE_CS8 4435
    #define NOTE_D8  4699
    #define NOTE_DS8 4978
    TimerSerial mySerial;
    int speakerPin;
    // Начальные установки
    void setup() {
      speakerPin = 14; // контакт 1.6 (или 14) у нас подключён к бибикалу
      mySerial.begin();
      mySerial.println("Welcome to CommitBeep 1.0");  
      pinMode(speakerPin, OUTPUT);
    }
    void playTone(int tone, int duration) {
      for (long i = 0; i < duration * 1000L; i += tone * 2) {
        digitalWrite(speakerPin, HIGH);
        delayMicroseconds(tone);
        digitalWrite(speakerPin, LOW);
        delayMicroseconds(tone);
      }
      digitalWrite(speakerPin, LOW);
    }
    // Бибикало
    void beep(int melody) {
      switch ((int)melody) {
        case '2': {
          int mel[] = {NOTE_C4, NOTE_G3, NOTE_G3, NOTE_A3, NOTE_G3};
          int noteDurations[] = {4,8,8,4,4};
          for (int thisNote = 0; thisNote < 4; thisNote++) {
            int noteDuration = 1000/noteDurations[thisNote];
            playTone(mel[thisNote], noteDuration);
          }
          break;
        }
        case '3': {
          int mel[] = {NOTE_C4, NOTE_G3, NOTE_G3, NOTE_A3, NOTE_G3};
          int noteDurations[] = {4,8,8,4,4};
          for (int thisNote = 0; thisNote < 4; thisNote++) {
            int noteDuration = 1000/noteDurations[thisNote];
            playTone(mel[thisNote], noteDuration);
          }
          break;
        }
        default: {
          int mel[] = {NOTE_C4, NOTE_G3, NOTE_G3, NOTE_A3, NOTE_G3};
          int noteDurations[] = {4,8,8,4,4};
          for (int thisNote = 0; thisNote < 4; thisNote++) {
            int noteDuration = 1000/noteDurations[thisNote];
            playTone(mel[thisNote], noteDuration);
          }
        }
      }
    }
    // Главный цикл
    void loop() {
      while (mySerial.available()) {
        char inChar = (char)mySerial.read(); 
        beep(inChar);
        delay(100);
      }
    }
    


    We connect, fill, open the terminal window, write 1 there, and listen to the default melody.



    Task Manager

    Oddly enough, but we will use the task scheduler for background execution of our PHP script.

    We’ll write a CMD file that PHP calls and the script itself:
    D:\denwer\usr\bin\php5.exe D:\denwer\home\test\www\commit_beep\index.php

    And so that this farm doesn’t piss off the black console window, we will use a simple hidcon utility from Andrei Grechkin.

    Scheduler Connection:



    Finishing touches

    By itself, everything works and zealously with every commit. But the table doesn’t look very beautiful. It remains to wrap our new piece of iron in a nice plastic case, having worked a bit with an office knife and electrical tape:




    Summary

    One day to develop from the idea to the finished device. An interesting and exciting fight against pitfalls and an introduction to Energia and the MSP430.
    The project budget ~ 200-300 rubles.

    Sources on github .

    Update: Added support for RTTTL - melodies in hard mode UART.
    In order to enable hard mode, you need to drag the RT / TX jumpers (Thanks BoxaShu ).
    Updated source codes.

    Also popular now: