Research1456.htm, Research1456.class and Engine1456.class files

Research1456.htm, Research1456.class and Engine1456.class files.

William Overington

Here are links to the files needed to run the Research1456 1456 applet landscape together with a copy of the source code of the HTML file. In order to run your own 1456 object code programs using this 1456 applet landscape, please download to a directory of your computer the files Research1456.htm, Research1456.class and Engine1456.class. Make a copy of Research1456.htm with a different name and then use a text editor, such as Notepad, to edit the source code of this newly created copy of the file Research1456.htm and then view that file in a browser. Please note that Research1456.htm on its own will just display text boxes, buttons, scrollbars and a blank central graphics display area and will do nothing when buttons are clicked or when the scrollbars are moved. This is because it is a blank landscape ready for 1456 programmers to add 1456 object code into a copy of it. I have prepared two example files, customizing the system as demonstrations. The mouse press function is active for both demonstrations. When using the system it is not advisible, other than as a test to observe the effect, to empty any of the text boxes and then press a button or click the mouse before adding anything back into the text box. The system updates the memory of the 1456 engine from the values in the text boxes when each button click, scrollbar movement or mouse click occurs.

Research1456.htm

There is one other matter that I need to mention and that is the matter of the typeface used in this 1456 applet landscape. I have used 12 point Arial as the font for this 1456 applet landscape. Readers who already have the Arial typeface on their system may find that they have not got the most recent version. The Microsoft Corporation very generously provides a free download facility for a number of fonts at the following web page.

Microsoft Corporation free fonts download page

The demo1.htm file has the following demonstrations. At start up the message "Please click the mouse!" is displayed on the screen. Start up also then moves the drawing pen to a point in the screen as the start point for the effect of the two rightmost scrollbars, which is described below. Clicking the mouse on the yellow background causes a blue circle centred on the click point to be shown. Actually, it is the act of pressing the mouse button down that causes the circle to be drawn. As well as clicking at various points on the background generally, readers might like to try clicking near the edges of the applet display area and near buttons to observe the effects of so doing.

The values of the two leftmost scrollbars are copied into the top two text boxes whenever these two scrollbars are moved. This is achieved by copying the value of the scrollbar from the mi1456 memory location where it is stored, converting it to a double type floating point number and then storing it in the md1456 memory location from where the value to be placed in the text box will be taken when control is handed back to the 1456 applet landscape.

The four buttons are programmed to carry out computations on the numbers in the top two text boxes and place the result in the third text box. Numbers may be entered into the top two text boxes either manually or by using the two leftmost scrollbars.

The two rightmost scrollbars are used to draw lines on the screen. The very rightmost scrollbar is a y coordinate and the rightmost but one scrollbar is an x coordinate. The colour of the line is decided by the value of the number in the fourth text box. The colour 4 is the same as the background and so can be used to rub out. Using the number -1 can produce a movepen effect without drawing a line and without rubbing out.

Hopefully these examples will give a good demonstration of the possibilities.

The demo2.htm file uses some accented characters in order to demonstrate what can be done and as a test to show whether an up to date font is being used. In the event that a character is not available on the computer that the user is using, the accented characters may show as a vertical line or as a square. Please know that it is possible for some accented characters such as the e acute of French to show correctly but for other characters, such as the C circumflex of Esperanto not to show correctly with an older font.

Clicking the mouse causes a box whose corner coordinates are given by the positions of the four scrollbars to be drawn.

Please note that not all of the text boxes are used in this demonstration.

For both of these demonstrations, analysing the source code of the HTML files may prove useful to people learning to use 1456 object code.

Please remember that all of the differences between demo1.htm and demo2.htm are produced by differences in the 1456 object code in the HTML files.

It is hoped that readers may wish to try producing their own demonstrations.

Here is the source code of the file Research1456.htm.

<html>
<head>
</head>
<body bgcolor="#804000">
<p align=center>
<applet code="Research1456.class" width=700 height=400>
The button names are a feature of the programming
of this particular applet landscape.
<param name="BUTTON01" value="1">
<param name="BUTTON02" value="2">
<param name="BUTTON03" value="3">
<param name="BUTTON04" value="4">
<param name="SOFTWARE01" value="1:H 51:H">
<param name="SOFTWARE02" value="52:H">
<param name="SOFTWARE03" value="53:H">
<param name="SOFTWARE04" value="54:H">
<param name="SOFTWARE05" value="81:H">
<param name="SOFTWARE06" value="82:H">
<param name="SOFTWARE07" value="83:H">
<param name="SOFTWARE08" value="84:H">
<param name="SOFTWARE09" value="41:H">

In operation, Research1456.class provides 10 entry points.
1: is for start up.

51: 52: 53: and 54: are for the buttons, from top to bottom.

81: 82: 83: and 84: are for the scrollbars, from left to right.

41: is for the mouse being pressed.

If the input to the text boxes is numerical, then
the values from the text boxes, from top to bottom,
are available in doubles 1, 2, 3 and 4 of the 1456
engine.
If the input to any text box is not numerical then
the value 0.0 is used for storage in the
corresponding double of the 1456 engine.
In all cases, regardless of whether the input to
the text boxes is numerical or not numerical,
a copy of the text entered is available in strings
1, 2, 3, 4 of the 1456 engine.
The strings are loaded into the 1456 engine using
the loadStringFromString method of the 1456 engine
and so 'u sequences are converted to unicode
characters as they enter the 1456 engine. 

The values from the scroll bars, from left to right,
are available in integers 1, 2, 3 and 4 of the
1456 engine.
The scrollbars are set initially at 0 and can have
values from -100 to +100.

The position of the mouse at a mouse press are placed
in integers 5 and 6, x and y respectively.

The shift key being down at the mouse press causes
a 1 to be placed in integer 7.
The shift key being up at the mouse press causes
a 0 to be placed in integer 7.

The control key being down at the mouse press causes
a 1 to be placed in integer 8.
The control key being up at the mouse press causes
a 0 to be placed in integer 8.

The alt key being down at the mouse press causes
a 1 to be placed in integer 9.
The alt key being up at the mouse press causes
a 0 to be placed in integer 9.

There is a software interrupt service routine
provided.
It is just provided so that users may try it out
if they choose.
The command 1? will, for this particular 1456
applet landscape, place the string
"The 1456 engine in action."
into ms1456[19]. 

</applet>
<br>
</body>

Readers are invited to send feedback by email. Please email the author to send details of usage, stating which type of computer is being used. In particular, I have only tried this on two PCs and would appreciate knowing how the system works on other platforms.

1456 object code