smallbasic.doc

smallbasic for linux

Console
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\t		tab (32 pixels)
\a		beep
\r\n	new line (cr/lf)
\xC		clear screen
\e[K	clear to EOL
\e[0m	reset all
        attributes to
		their defaults

\e[1m	set bold on
\e[4m	set underline on
\e[7m	reverse video
\e[21m	set bold off
\e[24m	set underline off
\e[27m	set reverse off
\e[3nm  set foreground
        color. where n:

        0 black
        1 red
        2 green
        3 brown
        4 blue
        5 magenta
        6 cyan
        7 white

\e[4nm  set background
        color.
		(see set foreground)

PalmOS only:

\e[8nm	(n=0..7)
        select system font
\e[9nm	(n=0..3)
        select buildin font
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?|PRINT [expr|str [{,|;}
            [expr|str]] ...

Displays a text or the value
of an expression.
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CAT(x)

Returns console codes

0 - reset
1 - bold on
2 - underline on
3 - reverse on

PalmOS only:
80..87 - select system font
90..93 - select custom font

Example:
? cat(1);"Bold";cat(0)
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INPUT [prompt {,|;}]
      var[, var [, ...]]

Reads from "keyboard" a text
and store it to variable.
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INPUT$(len[,fileN])
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CLS

Clears the screen.
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AT x,y (in pixels)

Moves the console cursor
to the specified position.

x,y are in pixels
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LOCATE y,x

Moves the console cursor
to the specified position.

x,y are in character cells.

File system
____________________________

Special file names:

"COM1:[speed]" -
  Serial port 1

Non PalmOS:
"COM2:[speed]" - 
  Serial port 2

Example:

OPEN "COM1:" AS #1

OPEN "COM2:38400" AS #2
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FREEFILE

Returns an unused file
handle
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OPEN "file" [FOR {INPUT|
             OUTPUT|APPEND}]
             AS #fileN

Opens a file or device
____________________________

CLOSE #fileN
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EXIST(fileName)

Returns true if the fileName
exists
____________________________

EOF(fileN)

Returns true if the file
pointer is at end of the
file
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PRINT #fileN{,|;} var1
                     [,varN]
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LINEINPUT #fileN{,|;} var$
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INPUT$(len[,fileN])
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SEEK #fileN{,|;} pos

Sets file position for
the next read/write
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SEEK(fileN)

Returns the current file
position
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LOF(fileN)

Returns the length of file
in bytes

For devices; returns the
number of available data
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KILL "file"

Deletes the specified file


Graphics & Sound
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Colors:
Mono: 0=black, 15=white,
      any=gray
2bit: 0=black, 15=white
      1-6,8=dark-gray,
      7,9-14=light-gray
4bit: 16 colors of gray
8bit: 16 Standard VGA colors

STEP keyword:
The STEP keyword calculates
the next x,y parameters 
relative to current position
____________________________

ARC [STEP] x,y,r,
       astart,aend[,aspect]
       [COLOR color]

Draws an arc

astart,aend = first,last
angle in rads.
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CHART {LINECHART|BARCHART}
     , array() [, {0|1|2|3}
     [, x1, y1, x2, y2]]

Draws a chart of array
values in the rectangular
area x1,y1,x2,y2

type:
0 = simple
1 = with marks
2 = with ruler
3 = with marks & ruler
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CIRCLE [STEP] x,y,r
           [,aspect]
           [COLOR color]
           [FILLED]

Draws a circle/ellipse.
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COLOR fg [, text_bg]

Changes the current pen
color
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DRAWPOLY array() [,x-origin
     ,y-origin [, scalef]]
     [COLOR color]

Draws a polyline

even elements for x
       (starting from 0)
odd elements for y
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LINE [STEP] x,y
           [{,|STEP} x2,y2]
		   [COLOR color]

Draws a line
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PSET [STEP] x,y
              [COLOR color]

Draw a pixel at x,y position
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RECT [STEP] x,y
           [{,|STEP} x2,y2]
           [COLOR color]
		   [FILLED]

Draws a rectangular 
parallelogram
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TXTW(s), TXTH(s)

Returns the text 
width/height of string s
in pixels
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BEEP

Generates a beep sound
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PLAY string

Play musical notes

A-G[-|+|#][nnn][.]
  Play note A..G
  +|# - sharp
  - - flat
  . - multiplier 1.5

On - Octave 0..6
<  - Moves down one octave
>  - Moves up one octave

Nnn - Play note 0..84
  (0 = pause)

Pnnn - Pause 1..64

Lnnn - Length of note 1..64
  (1/nnn)
Tnnn - Tempo 32..255
  Number of 1/4 notes per
  minute.

MS - Staccato (1/2)
MN - Normal (3/4)
ML - Legato

Vnnn - Volume 0..100

MF - Play on foreground
MB - Play on background
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SOUND freq, dur_ms [, vol]

Plays a sound
Miscellaneous
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RANDOMIZE [int]

Seeds the random number
generator

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RND

Returns a random number
from the range 0 to 1
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LBOUND(array [, dim])
UBOUND(array [, dim])

Returns the lower/upper
bound of the 'array'

The parameter 'dim' is the
array dimension whose bound
is returned

Example:
DIM v1(-4 TO 7)
DIM v2(1 TO 2, 3 TO 4)

? LBOUND(v1):REM -4
? UBOUND(v1):REM 7

? LBOUND(v2):REM 1
? LBOUND(v2,2):REM 3
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CINT(x) - convert x to
  32b integer

CDBL(x) - convert x to
  64b real number
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PEN ON|OFF

Enables/Disables the
PEN/MOUSE mechanism.
____________________________

PEN(0..14)

Returns the PEN/MOUSE data.

Values:
0 - true (non zero) if there
  is a new pen or mouse
  event
1 - PEN: last pen-down x;
  MOUSE: last mouse button
  down x 
2 - Same as 1 for y
3 - true if the PEN is down;
  mouse left-button is
  pressed
4 - PEN: last/current x, 
  MOUSE: the current x
  position only if the left
  mouse button is pressed
  (like PEN is down)
5 - Same as PEN(4) for y

Mouse buttons (non PalmOS):

10 - current mouse x pos.
11 - current mouse y pos.
12 - true if the left mouse
  button is pressed
13 - true if the right mouse
  button is pressed
14 - true if the middle
  mouse button is pressed

____________________________

PAUSE [secs]

Pauses the execution for a
specified length of time, or
until user hit the keyboard.

Mathematics:
____________________________

All angles are in RADs.

ABS(x) - Absolute value of x
COS(x) - Cosine of x
SIN(x) - Sine of x
TAN(x) - Tangent of x
ACOS(x) - Arc cosine of x
ASIN(x) - Arc sine of x
ATAN(x) - Arc tangent of x
ATAN2(x,y) - Arc tangent
  of two variables

Hyperbolic functions:

COSH(x), SINH(x), TANH(x)
ACOSH(x), ASINH(x), ATANH(x)

EXP(x) - the value of e
  raised to the power of x
LOG(x) - natural logarithm
  of x
LOG10(x) - the base-10
  logarithm of x

POW(x,y) - x raised to
  power of y
SQR(x) - square root of x

INT(x) - rounds x downwards
  to the nearest integer
FIX(x) - rounds x upwards
  to the nearest integer
ROUND(x [,decs])
  rounds the x to the
  nearest integer or
  fp with 'decs' decimal
  digits.

SGN(x) - sign of x
  +1 for positive,
  -1 for negative and
   0 for zero

DEG(x) - rads to degrees
RAD(x) - degrees to rads

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MAX(...), MIN(...)

Maximum/Minimum value of
parameters. Parameters can
be anything (arrays, ints,
reals, strings).

Example:
? MAX(3,4,8)
? MIN(array(),2,3)
? MAX("abc","def")
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Strings:
____________________________

LEN(s) - length of string
SPACE$(n) - returns a string
  of 'n' spaces

OCT$(x) - octal value string
  of x
HEX$(x) - hexadecimal value
  string of x
VAL(s) - numeric value of
  string s
STR$(x) - convert x to 
  string
ASC(s) - ASCII code of first
  character of s
CHR$(x) - returns one-char
  string of character with
  ASCII code x
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LCASE$(s), UCASE$(s)

Converts the string s to 
lower/upper case

Example:
? LCASE$("Hi"):REM hi
? UCASE$("Hi"):REM HI
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LTRIM$(s), RTRIM$(s)

Removes leading/trailing
spaces from string s

? LEN(LTRIM$("  Hi")):REM 2
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LEFT$(s,n), RIGHT$(s,n)

Returns the n number of
leftmost/rightmost chars
of string s
____________________________

MID$(s, start [,length])

Returns the part (length)
of the string s starting
from 'start' position

If the 'length' parameter is
omitted, MID$ returns the
whole string from the pos.
'start'.
____________________________

INSTR([start,] s1, s2)

Returns the position of the
first occurrence of the
string s2 into string s1
(starting from the position
'start')

If there is no match, INSTR
returns 0
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STRING$(len,{ascii|str})

Generic

Limits:
____________________________

Max. length of 
   code text line: 511 chars
Max. keyword length: 32 char
Max. num. of parameters: 64
Max. arrays dimentions: 4
Numeric value range: 64b FPN
Max. string size: 32KB
Max. number of file handles:
  PalmOS: 16
  Other: 256
INPUT/LINEINPUT limit: 255B
                   per call.

____________________________

Variables:
____________________________

There is no data types. All
user variables (include
arrays) are 'VARIANT'.

SB uses internaly 3 types
1. Integer (32bit)
2. Real    (64bit)
3. String  (<32KB)

Variable names can use any
alphanumeric characters,
and the '$'. The first char
of the name cannot be
a digit.
The symbol '$' is supported
for compatibility. Its use
is meanless.

For compatibility;
the arrays can have the
same names with simple
variables.
So x and x() are two
different variables.

Example:

a="123"
a$=1
? a<>a$
REM displays 1 (true)

DIM x(10)
x=1
x(1)=2
? x, x(1):REM displays: 1  2

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System Variables:
____________________________

OSVER  - OS Version
OSNAME - OS Name
SBVER  - SmallBASIC Version
PI     - 3.14..
XMAX,YMAX
       graphics display max.
BPP    - Bits per pixel

____________________________

Operators (by priority):
____________________________

( )       = parenthesis
-         = unary
^         = power

* / \     = mul, div, idiv
% MOD     = modulus

+ -       = add, sub

=> =<  = 
>= <= <>  = compare

AND & OR  |
NOT ! XOR ~
          = logical

:         = EOL

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Base convertion:
____________________________

&H|0x hex. ex: 0x1F + &H1F
&o|0o oct. ex: 0o33 = &o33
&b|0b bin. ex: 0b11 = &b11
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Subroutines/Functions:
____________________________

SUB name
  [([BYREF] par1 [,
  ...[BYREF] parN)]]

  LOCAL var[, var[, ...]]

END

FUNC name
  [([BYREF] par1 [,
  ...[BYREF] parN)]]

  LOCAL var[, var[, ...]]

END

Use function's name
to return the value.

Nested procedures/functions
are allowed (like Pascal).

Example:

FUNC f(x)
  FUNC f11
    FUNC f21
	f21=21
	END
  END
  FUNC f12
  f12=12
  END

? f11
? f21: REM ERROR
f=x+f11+f
END

The parameters are 
'by value' by default.
Use BYREF keyword for
'by reference'

Use the LOCAL keyword
for local variables.

You can send arrays as
parameters with ().

When using arrays as
parameters its better
to use them as BYREF. 

Example:
SUB FV(BYREF tbl())
...
END

' MAIN
DIM dt(128)
...
FV dt()


On a multi-section 
applications sub/funcs needs
declaration on the main
section.

Example:
#sec:Main
declare func f(x)

#sec:another section
func f(x)
...
end


Passing & returing arrays

Example:

func fill(a())
  local b(), i

  dim b(16)
  for i=0 to 16
    b(i)=16-a(i)
  next
  fill=b()
end

DIM v(4)
v()=fill(v())

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Statements:
____________________________

'|#|REM ...

Remarks.
The # can be used as remarks
only in the first pos. of
the text line.
____________________________

[LET] var = expr

Assign 'expr' to variable
'var'.

Example:
z=1
z="Change to string"

DIM v(4)
v2()=v()
z=v():REM make z copy of v()
____________________________

CONST var = expr

Assign 'expr' to variable
'var' and make it READ-ONLY.
____________________________

DIM var( [lower TO] 
             upper [, ...])

Creates an array.
____________________________

[LABEL] label

Defines a label. There are
two kinds of labels. Numeric
and alphanumeric.

Numeric labels does not 
needed the keyword LABEL,
but alphanumeric does.

Example:
1000 ? "Hello"

LABEL AlphaLabel
? "Hello"
...

GOTO 1000
GOTO AlphaLabel
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GOTO label

Branches to a specified
label.
____________________________

GOSUB label - RETURN

Branches to a old-style
subroutine. The subroutine
returns to GOSUB's next
instruction with RETURN.
____________________________

ON expr GOTO label-list
ON expr GOSUB label-list

Branches to one of the 
several locations, depending
of the value of the 'expr'.
____________________________

FOR var = expr TO expr
         [STEP expr] - NEXT

Repeats a code block for
a specified number of times.
____________________________

WHILE expr - WEND

WHILE/WEND code block, loops
while 'expr' is true.
____________________________

REPEAT - UNTIL expr

REPEAT/UNTIL code block, 
loops while 'expr' is false.
____________________________

IF expr  [THEN] -
         [ELSE|ELIF|ELSEIF]
         - ENDIF|FI

Executes a code block
depending on specified
conditions.
____________________________

IF expr THEN
          [num-label]|[...]
   [ELSE [num-label]|[...]]

Old-style inline-IFs.
____________________________

STOP|END

Stops the program execution.
____________________________

RESTORE label
READ var[, var ...]
DATA n[,n ...]

DATA specifies values to
be read by READ.

RESTORE specifies the
position of the next
data to be read.

READ reads values from
current data position.

Example:

RESTORE MyDataBlock
FOR I=1 TO 3
	READ v
	PRINT v
NEXT
END

LABEL MyDataBlock
DATA 1,2,3
____________________________

EXIT [FOR|LOOP|SUB|FUNC]

By itself exits from last
command block (loop, for
or routine)

FOR - Exit from the last
  FOR-NEXT loop

LOOP - Exit from the last
  WHILE/REPEAT loop

SUB - Return from the
  current routine

FUNC - Return from the
  current function

System
____________________________

FRE(0|-1|-2|-3)

Returns information about
system memory

 0 - free memory
-1 - largest block of
  integers
-2 - free stack
-3 - largest free block
____________________________

TICKS() - the system-ticks
  count

TICKSPERSEC() - the number
  of ticks per second
____________________________

TIMER - returns the number
  of seconds from midnight

TIME$ - returns the current
  time as string "HH:MM:SS"

DATE$ - returns the current
  day as string "DD/MM/YYYY"
____________________________

DELAY ms

Delay for a specified amount
of milliseconds
____________________________

CHAIN file

Runs another SB program

Example:
CHAIN "PROG2.BAS"
____________________________

RUN file

Runs an executable

PalmOS:
  the 'file' is the
  creator ID 

____________________________

Debug:
____________________________

TRON/TROFF

TRACE ON/OFF. When trace
mechanism is ON, the SB
displays each line number
as the program is executed
____________________________

LOGPRINT ...

PRINT to SB's logfile
____________________________

BCDUMP [len]

Displays the 'len' next
bytes of byte-code
____________________________

STKDUMP

Displays the SB's internal
executor's stack