WORKING WITH APPLE //e BASIC PART V by Frank Lemmen
In the previous episode of this continuing story, we ended with
the STOP command. Now, we'll take a look at the last of Apple
basic commands. So this is the last episode of the Dallas-a-like
series.
STORE
STORE array-name
This function is a tape function, so this is not relevant for
our emulator.
STR$
STR$(value)
Converts a value into a string.
TAB(
TAB(spaces)
An element of a print list, usable only in print lists.
TAB moves the print position to the declared number of spaces
form the left margin.
TAN
TAN(angle)
Returns the tangent of an angle expressed in radians.
TEXT
In the graphics of high res graphics modes TEXT, returns
operation to the full screen text mode of 24 lines.
THEN
IF condition THEN instruction.
TO
HPLOT TO X1,Y1 TO X2,Y2, TO........
TRACE
A debug aid, which displays the line number on the screen each
time a statement is executed. The number may be overwritten by
PLOT commands. The command can be terminated by CRTL-B or the
NOTRACE command.
USR
USR(argument)
This function passes an argument to a machine language
subroutine.
VAL
VAL(string value)
This function makes a numerical evaluation of a string. The
first character must be a possible number item, or a 0 is
returned.
VLIN
VLIN start-y, end-y AT x
In low res graphics, VLIN draws a vertical line from the line
designated as start-y to the line designated as end-y, and
located at the column designated as x.
VTAB
VTAB line
Moves the cursor to the specified line.
WAIT
WAIT Address, condtion, test-on
Used to insert a pause of controlled duration into a program.
The address is the decimal address of a location whose contents
is to be tested. The condition is a numerical value 0-255
inclusive, which specifies the bits to be tested. The test-on
value may be from 0-255. Effectively, this indicates whether
the test for each bit is to be made for 1s of 0s. If neither is
specified 0s are assumed.
XDRAW
XDRAW shape number AT x-coordinate, y-coordinate XDRAW shape nr.
Identical in construction to DRAW, but draws the shape in
complement to the color spcified by the most recent HCOLOR.
That was all, folks! I'm now searching for a new series. If you
have any suggestions, please jot them down on a piece of paper
and send it to the ST NEWS correspondence address.
Disclaimer
The text of the articles is identical to the originals like they appeared
in old ST NEWS issues. Please take into consideration that the author(s)
was (were) a lot younger and less responsible back then. So bad jokes,
bad English, youthful arrogance, insults, bravura, over-crediting and
tastelessness should be taken with at least a grain of salt. Any contact
and/or payment information, as well as deadlines/release dates of any
kind should be regarded as outdated. Due to the fact that these pages are
not actually contained in an Atari executable here, references to scroll
texts, featured demo screens and hidden articles may also be irrelevant.