;***********************************************************;
;......................... MiniDig .........................;
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; an Atari 2600 programming site based on Garon's "The Dig" ;
; which is now dead. The content here is made up mostly of .;
; selected posts from the [stella] mailing list.............;
; ..........................................................;
; If you're new to 2600 programming, you'll want to start ..;
; at the docs and links section.............................;
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| disassemblies | tricks | demos | tools | docs | links |
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tricks:
trick source binary original post comments
Reading Paddles paddles.txt . Thomas Jentzsch This is a really quick way to read a paddle in your kernel.
Reading Driving Controllers driving.txt . Thomas Jentzsch More super efficient controller reading code from Thomas.
48 Pixel Sprite bigmove.asm bigmove.bin Eckhard Stolberg Big sprite you can move all over the screen with the joystick. Source tweaked to work with current DASM.
Horizontal Repositioning battlezone.txt . Manuel Rotschkar (Polik) Very efficient routine for repositioning objects found in Battlezone. Explanation here.
Pitfall 2 Sound pitsound.zip pitsound.bin Andy Mucho Sound code similar to Pitfall 2 but without special hardware. Needs some work to be useful in a game, but has potential. Sounds best on a real Atari.
HMOVE Timing hmove.txt . Brad Mott A chart showing what HMOVE does when you execute it at odd times. This can help remove the black HMOVE lines or allow farther movement than normal with HMPx registers.
Scrolling Text scrltext.zip scrltext.bin Eckhard Stolberg Eckhard's efficient scrolling text demo.
No Flicker 13 Char Text 13ch4.asm 13ch4.bin Andrew Towers My 13 char text routine, optimized by Andrew Towers and Thomas. Displays 15 lines but will need conversion to indirect addressing for most applications.
No Flicker 13 Char + 2 Text 13_plus2.asm 13_plus2.bin Paul Slocum 13 char routine with 2 more characters off to the side. Good for inventory/options/score screens. Displays 13 lines.
VDEL Explained . . Eckhard Stolberg This explains how VDEL works and how it was intended to be used.
Skipdraw Explained skipdraw.txt . Dennis Debro Explanation of Thomas's Skipdraw kernal sprite routine. Note that the skipDraw branch will typically branch out of the kernel and then return to keep the cycles consistent.
Multi-Sprite Trick Explained . . Christopher Tumber Explanation of the RESPn trick as found in Galaxian and used in Space Instigators.
Inverted Graphics/
3 Color Score
score3x2.asm score3x2.bin Thomas Jentzsch By inverting the score digit graphics, fewer color writes are required and more colors are possible. This example wouldn't be possible if you tried to rewrite COLUP0 and COLUP1 3 times on each line.
Fractional Positioning . . Andrew Davie Objects can easily be moved fractions of pixels using 16-bit position variables. Andrew explains it in this post.


site maintained by Paul Slocum -- Contact me with any corrections or potential additions.