Wee Basic Manual

Welcome to

Wee Basic

A. Operation

NOTE: There is no ‘run’ command.  Press the A or START key to run your program.  Press ‘X’ to load a program (text) file and press ‘Y’ to save a program (text) file.  You can also use the dashboard on the bottom screen which contains icons to save, load and run a program (just tap the relevant icon with finger or stylus).

BREAK: hold ‘A’ and ‘Start’ at the same time to break a running program (eg if you get stuck in an infinite loop)

B. Commands/statements etc

1. Statements

rem

Description: leave a comment or remark in a program.

Usage: rem [any symbol or letter as a comment] *

Everything between “rem” and “*” is ignored by the interpreter.

Examples:

rem This is a program *
rem Hello.  The interpreter will ignore this so I can say whatever I want *

dim

Description: sets aside memory in the variable table for an array. In Wee Basic, each array must be initialised with dim or using the array will result in an error. There is a maximum of 100 numerical and 100 string variables. Each string array is limited to 30 members and each numerical array is limited to 100 members.

Usage: dim <variable name>(<number of elements>)

Examples:

dim astring$(5)
dim num(10)
for i=1 to 10
let num(i)=i+1
next

while/wend

Description: loops until a condition is satisfied.

Usage:

while <condition>
[block]
wend

<condition> is a boolean expression
Nested while statements are supported in Wee Basic

Examples:

let x=0
while x=0
let x=key()
wend

if/elseif/else/endif

Description: isn’t it obvious?

Usage:

if <condition> {and/or <condition> {and/or <condition>}… etc}
[block]
[elseif <condition>]
[block]
[elseif <condition>]
[block]
Etc..
[else] [block]
endif

<condition> is a boolean expression, eg >, <, = and <>
Nested ‘if’ statements are supported in Wee Basic

Examples:

input age

if age>12 and age<20 print 1 “you are a teenager”
endif

for/next

Description: isn’t it obvious?

Usage:

for <variable> = <number/variable> to <number/variable [<number/variable]
[block]
next

The syntax at the end, ie “[<number/variable]” is optional and provides a step function.

Nested ‘for’ statements are supported in Wee Basic

Examples:

for i=1 to 10
print 1 i
next

for j=1 to 20 [10]
next

(In this example, j will go from 1 to 11 to 21)

let

Description: Wee Basic requires ‘let’ for all assignments

Usage:

let <string variable> = <string expression>
or
let <number variable> = <number expression>

Examples:

let anumber=5
let astring=”Hello”
if a=5 let b=10
endif

goto

Description: move program execution to specified label

Usage: goto <label name>:

Examples:

lab start:
goto start:

gosub/return

Description: execute subroutine

Usage: gosub <sub name>:

Examples:

gosub start:
end

sub start:
print “This is the start.”
return

print/print at

Description: prints text on specified DS screen

Usage: print s [at x,y] <string or variable>, s is screen

at x,y is optional

Examples:

print 1 “Hello World”
print 0 at 5,5 “This is a program”
print 0 astring$

cls

Description: clears specified DS screen of text and graphics

Usage: cls s, s is screen

Examples:

cls 0
cls 1

end

Description: ends the basic program. Omitting ‘end’ will result in an error and so will placing anything after end (except for subroutines – see ’sub’)

Usage: end

input

Description: allows the user to input text until <return> is pressed

Usage: input <variable>

Examples: input a$

Note: buggy, better to use key()

lab

Syntax: lab <label name>:
see goto

sub

Syntax: sub <sub name>: [block] return

see gosub

plot

Description: Places a pixel on screen s at x,y

Usage: plot <s> <x>,<y>,<colour>

Note: colour is a number/variable 0-16  (0 is used to erase)

(See line statement for colours)

line

Description: Draws a line on screen s from x1,y1 to x2,y2

Usage: line <s> <x1>,<y1>,<x2>,<y2>,<colour>

Note: colour is a number/variable 0-16 (0 is used to erase)

Colour are:

black 1
blue 2
green 3
cyan 4
red 5
magenta 6
brown 7
white 8
gray 9
light blue 10
light green 11
light cyan 12
light red 13
light magenta 14
yellow 15
bright white 16

keyshow

Description: show the soft keyboard on the bottom screen if hidden

Usage: keyshow

keyhide

Description: hides the soft keyboard on the bottom screen if visible

Usage: keyhide

Note: keyhide MUST be used before displaying anything on the botton screen. Otherwise Wee Basic throws an error (reason is the user will not be able to see anything displayed if the keyboard is present).

createspr

Description: Creates a sprite specified by the file name on the screen specified at the specified coordinates.

Usage: createspr <number>,<screen>,<x>,<y>,<width>,<height>,<file name>

<file name> is a string or string variable. The file must be a gif file for a 256 colour sprite (greater colour depth will cause a crash). The file must be in the root directory of your card.  The others are numbers or number variables

movspr

Description: Moves an existing sprite specified by the number to new coordinates x and Y on the screen.

Usage: movspr <number>, <screen>, <x>,<y>

All input are numbers or number variables

delspr

Description: Deletes the specified sprite.

Usage: delspr <number>, <screen>

All input are numbers or number variables

vflip and hflip

Description: flips sprites vertically and horizontally.

Usage:

hflip <sprite no>,<screen>
vflip <sprite no>,<screen>

backgr

Description: Creates a background on the specified screen with the gif file specified by the file name.  The file must be 256 colours and in the root directory of your card.

Usage: backgr <screen>, <file name>

Note: <file name> is a string or string variable. The file must be a gif file. Screen is 0 or 1.

2. Sounds

- playmp3 [string] {string is file name}

or playmp3 [string],<filename> <volume>,<pan>,<bitrate>  (each is an integer or number variable)

File must be in the root directory of your card.

plays an mp3 file

- pausemp3

pauses the playing of an mp3 file

- contmp3

continues a paused mp3 file

3. Microphone

- micrec

records from the microphone
will automatically stop recording when buffer is full so no need to manually stop recording

- micpla

plays whatever has been previously recorded from the microphone

4. Expressions

Syntax: let <variable>=<expression>

int(<number expression>)
rnd(<number expression>)
sin(<number expression>)
cos(<number expression>)
tan(<number expression>)
log(<number expression>)
sqrt(<number expression>)
key() – gets key input

returns an integer value for keys pressed as follows:

X: 200
Y: 201
A: 202
B: 203
Left: 204
Right: 205
Up: 206
Down: 207
L: 208
R: 209
Start: 210
Select: 211

keyboard: ascii value

stx() – stylus x coordinate
sty() – stylus y coordinate
stt() – 1 if stylus touches screen, 0 if not

motx – motion x coordinate

moty – motion y coordinate

3. Math symbols

+, -, *, /, ^

4. Motion

- motion (initialises motion – throws an error if motion card is not detected

(see also expressions)

5. Examples

(a) Fun with colours

dim letter$(5)
let letter$(1)=”h”
let letter$(2)=”e”
let letter$(3)=”l”
let letter$(4)=”l”
let letter$(5)=”o”
rem hide the keyboard to use the bottom screen *
keyhide
print 0 at 0,14 “Wee Basic: Fun with colours”
print 0 at 0,15 “Keep pressing a button”
print 0 at 0,16 “to continue”
let j=4
rem test all new 16 colours *
for i=1 to 16
rem draw a line with each colour on each screen *
line 1 j,1,j,30,i
line 0 j,1,j,30,16-i
print 0 at 0,20 “J: “+j+ “i: “+i
let j=j+10
gosub getkey:
next
rem let’s test ‘;’ with print *
for e=1 to 5
print 1 letter$(e);
next
end

rem wait for a key to be pressed *
sub getkey:
let k=0
while k=0
let k=key()
wend
return

(b) Creating and flipping a sprite

createspr 1,1,50,50,32,64,”soldier.gif”
gosub getkey:
hflip 1,1
gosub getkey:
vflip 1,1
gosub getkey:
end

sub getkey:
let k=0
while k=0
let k=key()
wend
return

(Make sure you have a 32×64 sprite named “soldier.gif” in the root directory or this program will raise an error)

(c) Sound

print 1 “A – Pause mp3″
print 1 “B – Continue mp3″
print 1 “right – replay”
print 1 “higher volume/rate”
print 1 “left – exit”
print 1 ” “
let keya=202
let keyb=203
let right=205
let left=204
let vol=10
let pan=0
let rate=500
lab start:
let k=0
print 1 at 0,20 “Volume:”+vol
print 1 at 0,21 “pan: “+pan
print 1 at 0,22 “rate: “+rate
playmp3 “test.mp3″,
vol,pan,rate
while k<>right and k<>left
if k=keya pausemp3
endif
if k=keyb contmp3
endif
let k=key()
wend
stopmp3
let vol=vol+10
let rate=rate+50
if pan=0 let pan=64
elseif pan=64
let pan=127
elseif pan=127
let pan=0
endif
if vol>=127
let vol=10
endif
if k=right
goto start:
endif
end

(Make sure you have a file named test.mp3 in the root directory or this program will raise an error)

(d) Microphone

let keya=202
let keyb=203
let right=205
let k=0 let rec=0
while k<>keya
if k=right and rec=0
let rec=1
print 1 “Recording….”
micrec
endif
if k=keyb and rec=1
let rec=0
print 1 “Playing….”
micpla
endif
let k=key()
wend
end

(e) rem test

rem hello this should all be ignored*
print 1 “Helllo world”
end

(f) sprite demo

let soldier=1
let bottom=0
let top=1
let keya=202
let keyb=203
let right=205
let left=204
let soldx=5
let soldy=95

cls 1
keyhide
cls 0

gosub topback:
gosub botback:
gosub soldspr:

lab start:

let k=0
let k=key()

if k=keyb
gosub jump:
endif

if k=keya
goto finish:
endif
if k=right or k=left
gosub movsold:
endif

goto start:

lab finish:
end

sub key:
let k=0
while k=0
let k=key()
wend
return

sub topback:
backgr top,”island.gif”
return

sub botback:
backgr bottom,”lake.gif”
return

sub soldspr:
createspr soldier,bottom,
soldx,soldy,32,64,
“soldier.gif”
return

sub movsold:
if k=right
let soldx=soldx+20
movspr soldier,bottom,
soldx,soldy
endif
if k=left
let soldx=soldx-20
movspr soldier,bottom,
soldx,soldy
endif
return

sub jump:
for i=1 to 4
let soldy=soldy-20
movspr soldier,bottom,
soldx,soldy
gosub delay:
next
for i=1 to 4
let soldy=soldy+20
movspr soldier,bottom,
soldx,soldy
gosub delay:
next
return

sub delay:
for j=1 to 10
next
return

(You need all of the gif files in the root directory for this to work)