Creating your own MLC programs:
-------------------------------

MLC programs are stored in BASIC programs with "MLC:" on the first
line.  Of course, like normal BASIC programs, you can write MLC
programs with the Graphlink software on a computer, or on the
calculator with the program editor.  For a general guide to
programming with MLC, go to www.dysfunction.earthforge.com (sorry about
the ugly green-and-white color scheme, our site was hacked), click the
"MLC" button on the left of the page, and follow the "Readme" link.
However, the readme is usually a few versions behind, so look at
syntax.txt for the details.  ;-)  If you can't figure something out,
look at the code of the sample programs.


Random important information:

(General)
Names of MLC programs can't be more than 7 characters
MLC programs can't be over 11 KB
All function/variable/sprite names are limited to 5 chars
The screen is cleared before the program is executed, so you don't need
	to put CLRS at the beginning
When counting line numbers in the error handler, only lines with
	commands or expressions are counted (most of the time, you don't
	need to worry about this, because the contents of the line with
	the error are shown - it works most of the time)
Any gfx operations involving points outside (0,0) and (95,63) will
	be skipped, except with sprites and bitmaps (see the
	next section)
Limits for data types are: 110 variables, 125 functions, 15 sprites,
	40 8x8 bitmaps (remember that if you use a lot of
	memory with large arrays or bitmaps, you might not be able to
	reach these numbers)

(Commands)
The upper limit for RNDM can't be above 1024
CLRS just clears the screen buffer, since the physical screen is
	cleared at the start of the program, and will only have an
	effect after a DRAW command
Sprites are clipped to the edges of the 96x64 screen


(Variables)
Array index starts at 0, arrays can have up to 255 elements
String vars allowed 35 chars each
8x8 and 16x16 bitmaps are allowed
Sprite positions can't be over 127 or under -127


(Pointers)
If an array variable is assigned to a pointer, "*PTR=1,2,3,4" and
	"#PIXT 0,0,*PTR(1)" won't work
Pointers can't be assigned to array elements or sprite properties
	("*PTR:@ARRAY(0)" and "*PTR:^SPR.X" don't work)
Pointers assigned to strings can't be used in the conditional
	expression after an IF command


Supported commands:

DATA, DEND, BITM, SPRT, CLSN, ARRY, SIZE, CLRS, TEXT, LINE, PIXL, PIXT,
DISP, DBMP, RECT, SHFT, DRAW, STOP, RCLP, GKEY, WKEY, PAUS, FNCT, FRUN,
FGOB, FEND, IIFF, THEN, IFND, RNDM, WRTE, READ, HALT, POLR, SUBS, RSET,
CINT, ABSL, WAIT, INPT, NMAP, TILE, CMAP, TCHK, DMAP


Memory management:

If you use large arrays or tilemaps, you might have to consider the
amount of memory they take up to avoid getting an "out of memory" error.
There are 4 areas of free memory for vars in MLC86: 2x 180-byte areas,
1x 300-byte area, and 1x 318-byte area.  The memory (in bytes) used by
each variable type is:

ints		2
strings		[length]+1
arrays		[size]*2+1
tilemaps	[x size]*[y size]*2+4
(sprites and bitmaps are stored in their own separate memory areas)

This means that you can't create an array with 200 elements, because even
though there's enough total memory to hold it, it's not going to fit into
any of the var memory areas.  You shouldn't have to worry about this most
of the time, though...


I know I've put this notice into all the other files here, but for
suggestions, help, comments, etc. please e-mail me at
straney@umbi.umd.edu or visit our website at www.dysfunction.earthforge.com.

Donald Straney / burntfuse