Atari BASIC - Atari BASIC Keywords

Atari BASIC Keywords

ABS	Returns the absolute value of a number
ADR	Returns the address in memory of a variable (mostly used for machine code routines stored in variables)
AND	Logical conjunction
ASC	Returns the ATASCII value of a character
ATN	Returns the arctangent of a number
BYE	Transfers control to the internal "Self Test" program ("Memo Pad" on early models)
CHR$	Returns a character given an ATASCII value
CLOAD	Loads from cassette tape a tokenized program that was saved with CSAVE
CLOG	Returns the common logarithm of a number
CLOSE	Terminates pending transfers (flush) and closes an I/O channel
CLR	Clears variables' memory and program stack
COLOR	Chooses which logical color to draw in
COM	Implementation of MS Basic's COMMON was cancelled. Recognized but the code for DIM is executed instead
CONT	Resumes execution of a program after a STOP at the next line number (see STOP)
COS	Returns the cosine of a number
CSAVE	Saves to cassette tape a program in tokenized form with fast method (short inter-record gap on tape) (see CLOAD)
DATA	Stores data in lists of numeric or string values
DEG	Switches trigonometric functions to compute in degrees (radians is the default mode) (see RAD)
DIM	Defines the size of a string or array (see COM)
DOS	Transfers control to the Disk Operating System (DOS); if DOS was not loaded, same as BYE
DRAWTO	Draws a line to given coordinates
END	Finishes execution of the program, closes open I/O channels and stops any sound
ENTER	Loads and merges into memory a plain text program from an external device, usually from cassette tape or disk (see LIST)
EXP	Exponential function
FOR	Starts a for loop
FRE	Returns the amount of free memory in bytes
GET	Reads one byte from an I/O channel (see PUT)
GOSUB	Jumps to a subroutine at a given line in the program, placing the return address on the stack (see POP and RETURN)
GOTO and GO TO	Jumps to a given line in the program. GOTO can be omitted in "IF ... THEN GOTO ..."
GRAPHICS	Sets the graphics mode
IF	Executes code depending on whether a condition is true or not
INPUT	Retrieves a stream of text from an I/O channel; usually data from keyboard (default), cassette tape or disk
INT	Returns the floor of a number
LEN	Returns the length of a string
LET	Assigns a value to a variable. LET can be omitted
LIST	Lists (all or part of) the program to screen (default), printer, disk, cassette tape, or any other external device (see ENTER)
LOAD	Loads a tokenized program from an external device; usually a cassette tape or disk (see SAVE)
LOCATE	Stores the logical color or ATASCII character at given coordinates
LOG	Returns the natural logarithm of a number
LPRINT	Prints text to a printer device (same result can be achieved with OPEN, PRINT and CLOSE statements)
NEW	Erases the program and all the variables from memory; automatically executed before a LOAD or CLOAD
NEXT	Continues the next iteration of a FOR loop
NOT	Logical negation
NOTE	Returns the current position on an I/O channel
ON	A computed goto - performs a jump based on the value of an expression
OPEN	Initialises an I/O channel
OR	Logical disjunction
PADDLE	Returns the position of a paddle controller
PEEK	Returns the value at an address in memory
PLOT	Draws a point at given coordinates
POINT	Sets the current position on an I/O channel
POKE	Sets a value at an address in memory
POP	Removes a subroutine return address from the stack (see GOSUB and RETURN)
POSITION	Sets the position of the graphics cursor
PRINT and ?	Writes text to an I/O channel; usually to screen (default), printer, cassette tape or disk (see LPRINT and INPUT)
PTRIG	Indicates whether a paddle trigger is pressed or not
PUT	Writes one byte to an I/O channel (see GET)
RAD	Switches trigonometric functions to compute in radians (see DEG)
READ	Reads data from a DATA statement
REM	Marks a comment in a program
RESTORE	Sets the position of where to read data from a DATA statement
RETURN	Ends a subroutine, effectively branching to the line immediately following the "calling" GOSUB (see GOSUB and POP)
RND	Returns a pseudorandom number
RUN	Starts execution of a program, optionally loading it from an external device (see LOAD)
SAVE	Writes a tokenized program to an external device; usually a cassette tape or disk (see LOAD)
SETCOLOR	Maps a logical color to a physical color
SGN	Returns the signum of a number
SIN	Returns the sine of a number
SOUND	Starts or stops playing a tone on a sound channel (see END)
SQR	Returns the square root of a number
STATUS	Returns the status of an I/O channel
STEP	Indicates the increment used in a FOR loop
STICK	Returns a joystick position
STOP	Stops the program, allowing later resumption (see CONT)
STRIG	Indicates whether a joystick trigger is pressed or not
STR$	Converts a number to string form
THEN	Indicates the statements to execute if the condition is true in an IF statement
TO	Indicates the limiting condition in a FOR statement
TRAP	Sets to jump to a given program line if an error occurs (TRAP 40000 cancels this order)
USR	Calls a machine code routine, optionally with parameters
VAL	Returns the numeric value of a string
XIO	General-purpose I/O routine (from "Fill screen" to "Rename file" to "Format disk" instructions)