Topic: Petit Computer Tutorials

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I'm writing tutorials for PetitComputer, and they start with the BASICs (get the pun?) then go to the more complex stuff. Depending on when you read it, it might be unfinished, or done. I'm adding to it as I learn, myself. Here's the URL:

http://www.petitcomputerbasic.blogspot.com

Also, here's the first part to it, to get you started. But, I won't post EVERYTHING here, just the first part, then you can just visit my blog.

PART 1 Learning Some Basic Commands For Your First Program:

In this tutorial you will be learning SMILEBASIC, a programming language. SmileBoom says that you are using BASIC, but they're wrong. BASIC is a family of programming languages, many versions that are very similar to each other have been created. SMILEBASIC was created by SmileBoom, but it's very similar to other BASIC programming languages. So, if you were to write a program with something that used another type of BASIC, then you'd probably still be able to understand most of it.

So, let's start with the basics (< See the pun there? The programming language is SMILEBASIC.) then we'll keep working up until it gets to the really complex, complicated stuff. So, you're basically about to learn a different language, in fact, you are, this is just a programming language. So, this will be different than just simply learning "Hola" means "Hello." But, once you get the hang of it, and you are able to control your DS and make something happen, you'll feel like you are so powerful, and can do anything with that little stylus in your hand!
So, I bet you're wanting to learn how to do, and get started, on something! Well, let's start with one very simple command: the print command. This command is used to print text in your little program. So, pull out your DS, open PetitComputer, and go into Edit mode. In the first line type this:

print "I'm learning my first command!"

Don't forget the quotes, because if you just have, "print I'm learning my first command!" then there'll be an error. So, after you've typed this, go into Run mode. Chances are, nothing happened. Well, that's because you need to run your little program you've got started. You can do this by typing, "Run" then pressing the A button, or pressing Enter. Then this should pop up:

I'm learning my first command!
OK

So there you have it! You did it! But don't worry, if this didn't happen, that's okay. Just go back and make sure you did everything correctly. If you want something other than "I'm learning my first command!" to pop up, then just replace the words below:

print "Type whatever you want here"

Way to go! You've learned one of the many, many commands on PetitComputer!
Well, I'm sure you're getting annoyed with the:

PetitComputer ver2.2
SMILEBASIC 1048576 bytes free
(C)2011-2012 SmileBoom Co.Ltd.
READY

What this is is just what version of PetitComputer it is, the programming language, how much space is free, and the copyright. Lastly the, "READY" is just stating that the program is ready to operate. If you want to get rid of this, and all other text on your program, type in in run mode:

CLS

That's all you have to do. Then, all that text will disapear, and only, "OK" will be left. But be careful! It'll get rid of ALL the text, so if there's something important you want to keep, don't do this! (I honestly don't know what you would want to keep on your DS screen though ) So, if you wanted to have everything erased, then some text to pop up you would type this in edit mode:

CLS
print "I don't know what to put in these quotes"

Then go into run mode and run it. Then all you should be left with is:

I don't know what to put in these quotes
OK

Now that's much neater isn't it? No I'll show you how to save and load your program. First, make sure everything's the way you want it in Edit Mode. Once everything's proofread, go into Run Mode and run it. Then type in:

Save "Test"

I saved it as "Test" but, you can call it whatever you like. Then to load your program simply type in Run Mode:

Load "Test"

It's as simple as that! If you forgot your file name, then press the X on the upper right and return to the Home Menu (But make sure you saved your work first if you were doing something; if you don't it'll be lost!). Then click View Gallery and all your programs, along with the sample ones, are in there. So if you called your program "Test" You'll see it as, "PRG : Test".

I think that'll be all for the first part of this tutorial! Thank you for reading, I hope this has helped you on your quest to making programs!

Try to accomplish this before going to the next part:

1. Clear your screen
2. Print something on your screen with the print command
3. Save your program
4. Be happy that you made a program! ^-^

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Here are 3 simple ways to slide text window.
all 3 shows basic idea of using different methods(sprite, BG layer, Graphic layer)

they simply put(and slide) window on top of grass field(which is rear BG layer).
and text output is simply done by PNLSTR command.

press any button to open and close text window.

here is sprite version.

ACLS
CLEAR

'turn off bottom panel.
PNLTYPE "OFF"

'make some grass field.
BGPAGE 1
BGFILL 1,0,0,31,23,33,8,0,0

'select lower screen for sprites.
SPPAGE 1

'make 64x32 sprite with white color (&HF).
'sprite bank name for lower screen is "SPS0" and "SPS1".
'64x32 size sprite is 32 blocks of tile.
CHRINIT "SPS0"
FOR I=0 TO 31
CHRSET "SPS0",I,"F"*64
NEXT

'setup 2 big 64x32 sprites.
'set order of priority to the behind of console.
'so text will appear on top of sprites.
SPSET 0,0,0,0,0,1,64,32
SPSET 1,0,0,0,0,1,64,32

'scale 200%
SPSCALE 0,200
SPSCALE 1,200

'put them outside of bottom part of screen.
SPOFS 0, 0,192
SPOFS 1,128,192

@MAINLOOP

'wait for button press
FOR I=0 TO 1:I=BUTTON():NEXT

'move sprites up slowly using interpolation time.
SPOFS 0, 0,128,10
SPOFS 1,128,128,10

'wait until sprite has finished moving.
FOR I=0 TO 1:I=!SPCHK(0):NEXT

'put some text
PNLSTR 1,18,"This is first line.",14
PNLSTR 1,20,"This is second line.",14
PNLSTR 1,22,"This is third line.",14

'wait for button press.
FOR I=0 TO 1:I=BUTTON():NEXT

'erase text with blank
PNLSTR 0,18," "*32,14
PNLSTR 0,20," "*32,14
PNLSTR 0,22," "*32,14

'move sprites down slowly using interpolation time.
SPOFS 0, 0,192,10
SPOFS 1,128,192,10

'wait until sprite has finished moving.
FOR I=0 TO 1:I=!SPCHK(0):NEXT

GOTO @MAINLOOP

it uses 2 big (64x32) sprites and they act as window.
sprite's priority has changed, so window sprites appear under the text.
by the way, you can set/change/load sprite for bottom screen.
sprite bank name for bottom screen is "SPS0" and "SPS1"
for example: LOAD "SPS0:MYSPRITE"
(note:unlike upper screen which has 512 sprites, bottom screen has only 118 different sprites.)

here is Graphic version.

ACLS
CLEAR

'turn off bottom panel.
PNLTYPE "OFF"

'make some grass field.
BGPAGE 1
BGFILL 1,0,0,31,23,33,8,0,0

'select lower screen for Graphic.
GPAGE 1

'set Graphic priority to the behind of console
'so text will appear on top of Graphic layer.
GPRIO 1

@MAINLOOP

'wait for button press
FOR I=0 TO 1:I=BUTTON():NEXT

'start drawing line from bottom part of screen.
'fill upward.
'since filling with single line is too slow,I used x4 thick filled line.
FOR I=192 TO 128 STEP -4
GFILL 0,I,255,I+3,15
VSYNC 1
NEXT

'put some text
PNLSTR 1,18,"This is first line.",14
PNLSTR 1,20,"This is second line.",14
PNLSTR 1,22,"This is third line.",14

'wait for button press.
FOR I=0 TO 1:I=BUTTON():NEXT

'erase text with blank
PNLSTR 0,18," "*32,14
PNLSTR 0,20," "*32,14
PNLSTR 0,22," "*32,14

'erase window by drawing line with clear color 0.
'starting from top part of window. erasing downward.
'it will look like window is moving down.
'for speed, i used x4 thick filled lines.
FOR I=128 TO 192 STEP 4
GFILL 0,I,255,I+3,0
VSYNC 1
NEXT

GOTO @MAINLOOP

it simply draws white filled box on bottom.
as you draw more filled box upward, it will look like sliding window.
window box is erased with another box with clear color 0
Graphic layer's priority has changed, so Graphic window appears under the text.

here is BG version.

ACLS
CLEAR

'turn off bottom panel.
PNLTYPE "OFF"

'select lower screen for BG.
BGPAGE 1

'make some grass field on rear BG layer..
BGFILL 1,0,0,31,23,33,8,0,0

'make window box just outside of bottom part of screen.
'use foreground BG layer, so it will hide grass field.
'using white blocks.
BGFILL 0,0,24,32,31,15,0,0,0

'and you can add cool window border frame if you want..
BGPUT 0,0,24,532,1,0,0
BGFILL 0,1,24,30,24,536,1,0,0
BGPUT 0,31,24,533,1,0,0
BGFILL 0,0,25,0,30,539,1,0,0
BGFILL 0,31,25,31,30,537,1,0,0
BGPUT 0,0,31,535,1,0,0
BGFILL 0,1,31,30,31,538,1,0,0
BGPUT 0,31,31,534,1,0,0

'this BG layer will wait outside of bottom part of screen and is ready to scroll up.

@MAINLOOP

'wait for button press
FOR I=0 TO 1:I=BUTTON():NEXT

'scroll foreground BG layer up slowly using interpolation time.
BGOFS 0,0,64,10

'wait until foreground BG layer has finished moving.
FOR I=0 TO 1:I=!BGCHK(0):NEXT

'put some text
PNLSTR 1,18,"This is first line.",14
PNLSTR 1,20,"This is second line.",14
PNLSTR 1,22,"This is third line.",14

'wait for button press.
FOR I=0 TO 1:I=BUTTON():NEXT

'erase text with blank
PNLSTR 0,18," "*32,14
PNLSTR 0,20," "*32,14
PNLSTR 0,22," "*32,14

'scroll foreground BG layer down slowly using interpolation time.
BGOFS 0,0,0,10

'wait until foreground BG layer has finished moving.
FOR I=0 TO 1:I=!BGCHK(0):NEXT

GOTO @MAINLOOP

it uses foreground BG layer and use it as window.
draw window box just outside of bottom of screen.
(you can add cool frame on window layer if you want)
it waits outside and will scroll up/down as needed.

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Uhh so here's yet another MML guide. This isn't an in-depth tutorial, just a sort of "quick start". Also, there are other ways to write MML in Petit Computer, but I'm going to do it the way I think is easiest: using DATA portions. This tutorial assumes that you have basic music experience, such as the ability to read music and understand simple notation/musical concepts (like scales). It also assumes that you know what a DATA section is (it's just a way to store data in textual form. There, now you know!). If you're ever lost at a particular Petit Computer command, you can look it up in the Petit Computer Manual. If you're not sure about octave designations, you can look here (I forget them all the time too).

So, we'll start with an empty program. The most basic stuff we're going to need right now is BGMCLEAR, BGMSETD, and a DATA section headed by a label. Here's what it'll look like:

BGMCLEAR 128
BGMSETD 128, @MYSONG

@MYSONG
DATA 0

The first line says "Whatever song you had as song 128... well I don't care about it. I want it GONE". Song 128 doesn't exist yet, but it's still a good idea to clear it just in case (just like clearing your variables at the start of your program). The next line says "Alright, go out and find @MYSONG and shove all that data into song 128". Well, if you look down at the label for our song, you'll see just one piece of data: 0. This represents the end of our song, so you should always stick that at the end. If you run this program, it doesn't really do anything. Let's start slow and add just a single note: C. What C will it be, some of you may ask? Well, we'll see.

BGMCLEAR 128
BGMSETD 128, @MYSONG
BGMPLAY 128

@MYSONG
DATA "C"
DATA 0

I added 2 lines: BGMPLAY 128 just tells the program to play the song 128. That's the song we're filling up, so it should play... well, our song. I also added DATA "C". Notice that the C is in double quotes: all MML should be surrounded by double quotes (making it a string type), except for the 0 at the end. It's very important that you DON'T put the 0 in quotes. So, go ahead and run the program. If you did it right, you should hear a nice Piano sound playing "middle C" (that's octave 4 if you're looking at that chart I linked to). This is rather important: this means that Petit Computer defaults to a piano and that it defaults to octave 4. But what if you don't want a piano? Well, let's look at the manual: if you jump down to page 40, you'll see the start of a very important table: the sound list. This isn't the usual "BEEP" sounds, but special MML sounds. If you look at the very first one, you'll see that it's an Acoustic Piano. That's the sound we just heard in our program, but let's change it to.... a Vibraphone (sound 11). Let's add one extra line to make it a Vibraphone, along with adding more notes:

BGMCLEAR 128
BGMSETD 128, @MYSONG
BGMPLAY 128

@MYSONG
DATA "@11"
DATA "CDEFG"
DATA 0

The line I added was DATA "@11". The @ tells the MML to start using the specified instrument from now on. What this means is that you can stick an @ followed by an instrument in the middle of a series of notes and it will switch instruments right there. Cool, right? Well, it's not always useful, so let's play our music. It should play the lower half of the C Major scale in a Vibraphone sound (not that it matters, it's just notes rising). Notice that I squashed all the notes together; in MML, this is how you do it. Some of you may start to wonder "Hey, there are multiple notes named A, B, C etc. How do I tell it to play one in a different octave?". Well, let's change the one line with the notes to look like this:

DATA "CDEFGAB<C"

If you play it, it should be the regular old C Major scale. That < in there tells Petit Computer to go up to the next octave. Remember, octaves start on C, and changing the octave wherever you want means that ALL notes following will be raised to the next octave. For instance, if we were to extend that line again:

DATA "CDEFGAB<CDEFG"

If you play your song now, you'll notice that the following DEFG after the < are higher than the original ones. This is because we went up to the next octave. Try moving the < around in that sequence of notes to see how it changes. So what about sharps and flats? Well, they're + and - respectively in MML. For instance, if we want to play the F Major scale instead, we'll change our DATA line to:

DATA "FGAB-<CDEF"

Remember, F Major has 1 flat (B flat), and that's exactly what we've put in MML. The flat/sharp follows the note, so it's read "B flat" or "B minus" if you like. Also notice where the < is this time: it's still before the C, but it's not in the same place as our C Major scale. Remember, the octave starts on C, so C is the first note in an octave. This means that if we just stick "C" there without having <, it will play a C lower than the "FGAB-" we had previously, which isn't what we want in a scale. Note that you don't ALWAYS need the < in front of a C, it's just when you're crossing an octave boundary. The opposite of < is >, which lowers the octave. Here's the whole F Major scale then:

DATA "FGAB-<CDEFEDC>B-AGFA<CFC>AF"

If you play it, you'll hear the standard "concert" version of the scale, in which you ascend, descend, and then do the same with the arpeggio. Next, we should probably add some note lengths. Right now, everything has been the default length, which is a quarter note. If you want to set the length of a note, just follow it with the number specifying the length. The first link has a list of all the lengths. For instance: 4=Quarter note, 8=Eighth note, 16=Sixteenth note, etc. OK, let's make "Mary Had a Little Lamb":

DATA "E4D4C4D4E4E4E2D4D4D2E4G4G2E4D4C4D4E4E4E4E4D4D4E4D4C1"

Yuck, look at all those 4's. Remember, 4 is the default note length, so you don't need to put it. Those 2's are half notes, and the 1 at the end is a whole note. The length of the note should always follow the note itself. What if we want to change the tempo, volume, and starting octave? Let's make our "Merry Had A Little Lamb" rather fast and really high (but a little quieter):

BGMCLEAR 128
BGMSETD 128, @MYSONG
BGMPLAY 128

@MYSONG
DATA "@11T240O6V80"
DATA "L4EDCDEEE2DDD2EGG2EDCDEEEEDDEDC1"
DATA 0

Woah, I changed a lot! Let's start at with the first: I added some stuff to the DATA line that had our instrument. Now we've got T240 which tells us to go at 240 beats per minute, O6 which tells us to start up at octave 6 instead of octave 4 (look at the chart to see how much higher that is on the scale), and V80 to bring down the volume. Volume can range from 0 to 127, so 80 is... uhhh we'll say 2/3 volume. Next, on the next line I added "L4" and removed all the 4's. The L4 tells Petit Computer that notes without a length should default to this length. You can use L commands wherever you want, and it'll only affect the notes following it (until another L is reached which changes it). Try inserting L's followed by a length at various places in the song to see how it changes it. Notice that the E2, G2, and C1 don't change even if you mess with the L's, this is because the L only alters notes that don't have a length. Let's jump ahead a little bit:

BGMCLEAR 128
BGMSETD 128, @MYSONG
BGMPLAY 128

@MYSONG
DATA ":0@11T240O6V80"
DATA "L4EDCDEEERDDDREGGREDCDEEEEDDEDC1"
DATA ":1@0T240O4V100"
DATA "L4EDCDEEERDDDREGGREDCDEEEEDDEDC1"
DATA 0

That was quite a jump, so let's look at each change individually. The first change was the line immediately following the @MYSONG, I added a :0 to the beginning. Petit Computer can play 8 streams of music simultaneously, so I'm telling the Vibraphone part to fill in the first stream (which is 0). This is the default, which is why we didn't need it before. However, if you look, it looks like I've duplicated the song. But, it you look at the third data line, you'll see :1, which means that all the data following it should go into the second stream (which is 1). Also notice that the second stream is a different instrument, louder, and in a different octave. If you go ahead and play the song, you'll hear that the first stream plays just like it always did, but the second stream is now the piano (from the @0 on the third data line) and louder (from the V100 on the third data line). This shows that each stream is fully independent: whatever you do on one will not affect the other. Lastly, if you look closely at the note portion, you'll see I put R's instead of 2. R just stands for rest, and it acts like any other note (except that it's silence). Thus, instead of holding the notes for a half note (the 2), I play a quarter note and then a quarter rest (which adds up to the same as a half note).

And that's all I have for the "Basics of MML". I'll post another time with the more advanced stuff, like shaping notes and other effects. Using just the stuff you've hopefully learned by now, you should be able to make some nice melodies. If you want to continue without me, you can look at the first link I posted to see every single MML command available. Just start throwing stuff into the "Mary Had A Little Lamb" song and see what happens!