Skip to main content

Make simple music program with beep(freq, duration) with Pascal

Pascal is my first programing language when I have studied in high school. It was really exciting for me. :)

The Pascal programming language was created by Niklaus Wirth in 1970. It was named after Blaise Pascal, a famous French Mathematician. It was made as a language to teach programming and to be reliable and efficient. Pascal has since become more than just an academic language and is now used commercially.

I tried to make a simple music program by using Lazarus IDE on MS Window 7, 64-bit. It frustrated me a few times how difficulty to use Sound command to make a sound. Sound did not work on my compiler and my platform anymore. So far, I just could use beep(freq, duration) from window unit to implement my work.

Here is my code. ;)
program mysong;

uses
   Windows,
   crt;
const
  C: Integer = 512;    { x = A * EXP(LN(2)/12)}
  C_: Integer = 542;
  D: Integer = 574;
  D_: Integer = 608;
  E: Integer = 644;
  F: Integer = 682;
  F_: Integer = 723;
  G: Integer = 766;
  G_: Integer = 812;
  A: Integer = 860;
  A_: Integer = 911;
  B: Integer = 965;

  WHITE: Integer = 1600;        {x = B/2}
  BLACK: Integer =  800;
  SINGLE: Integer = 400;
  DOUBLE: Integer = 200;
  TRIPLE: Integer = 100;

procedure play(freq,duration: Integer);
begin
     Windows.Beep(freq,duration);
end;
begin
   { A Time For US }
   Clrscr;
   play(A, SINGLE);
   play(C*2, SINGLE);
   play(B, SINGLE);
   play(E, BLACK + SINGLE);

   play(E, SINGLE);
   play(G, SINGLE);
   play(E, SINGLE);
   play(A, BLACK + SINGLE);

   play(A, SINGLE);
   play(G, SINGLE);
   play(F, SINGLE);
   play(G, BLACK + SINGLE);

   play(G, SINGLE);
   play(F, SINGLE);
   play(E, SINGLE);
   play(D, BLACK + SINGLE);

   play(E, DOUBLE);
   play(D, DOUBLE);
   play(C, SINGLE);
   play(D, SINGLE);
   play(E, BLACK + SINGLE);

end. 

I just chose frequency's Do note is 512. Next, I inferred the frequency of other notes by "afterNote = beforeNote * EXP(LN(2)/12)".

Reference:
[1]. http://kon-phum.com/tutors/pascal/programming_pascal_learn01.html
[2]. http://stackoverflow.com/questions/23249175/how-to-use-sound-in-pascal

Comments

Popular posts from this blog

Styling Sort Icons Using Font Awesome for Primefaces' Data Table

So far, Primefaces has used image sprites for displaying the sort icons. This leads to a problem if we want to make a different style for these icons; for example, I would make the icon "arrow up" more blurry at the first time the table loading because I want to highlight the icon "arrow down". I found a way that I can replace these icons with Font Awesome icons. We will use "CSS Pseudo-classes" to achieve it. The hardest thing here is that we should handle displaying icons in different cases. There is a case both "arrow up" and "arrow down" showing and other case is only one of these icons is shown. .ui-sortable-column-icon.ui-icon.ui-icon-carat-2-n-s { background-image: none; margin-left: 5px; font-size: 1.1666em; position: relative; } .ui-sortable-column-icon.ui-icon.ui-icon-carat-2-n-s:not(.ui-icon-triangle-1-s)::before { content: "\f106"; font-family: "FontAwesome"; position: ...

[Snippet] CSS - Child element overlap parent

I searched from somewhere and found that a lot of people says a basic concept for implementing this feature looks like below: HTML code: <div id="parent">  <div id="child">  </div> </div> And, CSS: #parent{   position: relative;   overflow:hidden; } #child{   position: absolute;   top: -1;   right: -1px; } However, I had a lot of grand-parents in my case and the above code didn't work. Therefore, I needed an alternative. I presumed that my app uses Boostrap and AngularJs, maybe some CSS from them affects mine. I didn't know exactly the problem, but I believed when all CSS is loaded into my browser, I could completely handle it. www.tom-collinson.com I tried to create an example to investigated this problem by Fiddle . Accidentally, I just changed: position: parent; to position: static; for one of parents -> the problem is solved. Look at my code: <div class="modal-body dn-placeholder-parent-positi...

JSF, Primefaces - Invoking Application Code Even When Validation Failed

A use case I have a form which has requirements as follow: - There are some mandatory fields. - Validation is triggered when changing value on each field. - A button "Next" is enable only when all fields are entered. It turns to disabled if any field is empty. My first approach I defined a variable "isDisableNext" at a backend bean "Controller" for dynamically disabling/enabling the "Next" button by performing event "onValueChange", but, it had a problem: <h:form id="personForm"> <p:outputLabel value="First Name" for="firstName"/> <p:inputText id="firstName" value="#{person.firstName}" required="true"> <p:ajax event="change" listener="#{controller.onValueChange}" update="nextButton"/> </p:inputText> <p:outputLabel value="Last Name" for="lastName"/> <p:i...

How to convert time between timezone in Java, Primefaces?

I use the calendar Primefaces component with timeOnly and timeZone attributes for using only hour format (HH:mm). Like this: <p:calendar id="xabsOvertimeTimeFrom" pattern="HH:mm" timeOnly="true" value="#{data.dateFrom}" timeZone="#{data.timeZone}"/> We can convert the value of #{data.dateFrom} from GMT/UTC time zone to local, conversely, from local time zone to GMT/UTC time zone. Here is my functions: package vn.nvanhuong.timezoneconverter; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; import java.util.TimeZone; public class TimeZoneConverter { /** * convert a date with hour format (HH:mm) from local time zone to UTC time zone */ public static Date convertHourToUTCTimeZone(Date inputDate) throws ParseException { if(inputDate == null){ return null; } Calendar calendar = Calendar.getInstance(); calendar.setTime(inputDate); int ...

Build Dynamic Forms in AngularJS Directives

We wanted to build a dynamic form that has some types of elements such as text field, text area, label, date picker, combobox, file uploader, etc. Beside that, the form is dynamic because basing on the provided configuration data, it should render our expected GUI. We conducted a  research with two options: building our own directives or using a third-party directives. - Approach 1: using a third-party directives  + Google keyword: " build dynamic forms directives + angular third party "  + This idea met our idea: " http://blog.backand.com/build-dynamic-forms/ ", but it's not free to use.  + This 3rd-party was possible:  http://schemaform.io/ Schema form hello world app:  http://plnkr.co/edit/7Oqxxl?p=info - Approach 2: building our own directives We chose this approach because it looks more simple than using "schema form" 3rd-party and we thought that we can confidently handle it. Example:   http://codepen.io/cavoirom/pen/meJBxv?edit...