WORKING ON ][ IN A MAC by Frank Lemmen
In the previous issue of our ST NEWS you could read the first
episode of this article. This time I will continue to give you
the Apple ][ basic keywords in alphabetic order.
The last keyword in the previous episode was: HOME
So we continue with the following keywords:
HPLOT x,y HPLOT TO x,y
HPLOT x1,y1 TO x2,y2 TO x3,y3.....
Used to plot or draw in the high resolution graphics mode.
HPLOT must be preceded by HGR of HGR2 to avoid overwriting the
program and its data. An attempt to plot outside the limits (x
from 0 to 279,y from 0 to 191) produces an error.
Used to set the print position to the indicated value, which
must be in the range 0 to 255.
HTAB cannot be used as an item in a print list. Precede and
follow it with a semicolon to control the print position, which
may precede an item already printed on the same line.
IF condition then....
IF condition then goto...
IF condition goto....
Selects the peripheral or device plugged into a master board for
The value of the slot may be a number, variable, or an
The slots and devices are numbered 1-7 inclusive, and the values
must be within this range.
IN#0 indicates that input will be form the keyboard.
The instruction boots the disk if the disk controller is present
at the specified slot.
If you type a value between 8-255 the may cause a system hang.
Used to request an input (normally indentified on the screen by a
string in quotes), and accept the values of the variable of
Returns the largest integer that is less than equal to the
evaluated expression, current value of variable, or supplied
Use to reverse the video output.
LEFT$(object string,character select)
LEN (string expression)
LEN returns the length of the string. IF the string is greater
than 255 LEN returns an error.
LIST LIST line number
LISt line number1, line number2
Use control C to stop list. Use controls S to pause list any key
Originally the apple ][ works with a taperecorder. If you wanted
to load something form disk you typed in the parameters. Since
our ST cannot handle a taperecorder the LOAD command can normally
used without any parameters.
Returns the natural algorhythm of the variable.
Sets the address of the the lowest memory available to a basic
To see the current value, use PRINT PEEK(106)+256*PEEK(105)
MID$(object string, left char.,number char. select)
MID$(object string, left char. select)
Deletes the current program in memory.
NEXT variable name
NEXT variable name,variable name....
Sets the video display back to normal (the opposite of INVERSE)
The relational inverting operatro NOT converts a logical true
value (1) to logical false value (0), and vica versa.
Terminates a debug mode set up by TRACE, wich is used to print
line numbers on the screen tracing program execution.
ON condition GOTO line(s)
ON condition GOSUB line(s)
ONERR GOTO linenumber
Use to avoid having an error message printed and execution halted
when an error occurs in program execution.
Relation 1 OR relation 2
The arithmetic logical operator OR assumes the value true if
either relation 1 or relation 2 is true, or if both relations are
PDL (paddle number)
This command cannot be used on the emulator.
Next time more command hints and tips..........
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.