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I disassembled Slither

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Once again, but this was a bit different.

First off to say is that I did this for my education after I said I was taking a break.
I am working on two projects that have nothing to do with disassembling unless I needed a routine or two.

In any case, I like sharing my work free of charge.  I invest in you and you return that by creating more games.  Plus hitting the like button, please subscribe....


I changed this up a bit.

I created some macros to automate a most of this work.  I also updated it to act as if it were real hardware.

Now, my disassembler automatically references and labels all BIOS calls.  It also initializes the entire 1k of memory as $7000 even if it is $6000.  Meaning it will automatically remap cartridges using $6000 to $7000.   The BIOS starts at $0000 and only 8k, Ram at $7000 and only 1k, and Carts of any size start at $8000.  The stack pointer and PC counters also are now properly referenced.

I updated my IDE to clean up and left justify the code for readability.

I am now adding Sound definitions so you can track where each specific sound is being referenced.  This should help you track down routines for your own work.  This is so much easier than going to the Sound Table and looking up which sound 0BH is or some deal like that.

Again, I am trying to label as much as possible which will include RAM locations at some point.


This disassembly has been heavily labeled and some of it may be incorrect as far as the function.  To be fixed at a later date.

Most everything has been identified but at the time of this writing I did not reference the snake movement routines but the general area is there along with the music, patterns and other sound effects.  I did my best to outline the main loop and pause button.


I spent a good amount of time on this and credit goes to me.  Do not sell my work.


I did the usual tests by scrambling up the routines in most every way following proper Z80 structure and it assembled with no issues.  If you find something broken then we can work together on fixing it.

It would be greatly appreciated if CoolCV is looked at for the Spinner Emulation.  I am pretty sure the Main gun or whatever it is is not supposed to fly off to the side when you press F5.  Ever since I started testing Spinner Routines this happens.  If I had to bring it to someones attention I would say that something is not being initialized to zero.  Or maybe it's just me.

Assemble with drag and drop on TNIASM or use the DOS prompt.

I plan on revisiting this disassembly in the future to make it better but for now it should be transportable without issue.

I also found two routines that did not have any references so they were removed for a savings of 60 bytes.

I did not pad this one so if you want to assemble this to 16k you will have to add a few bytes.


So here you go,

Slither by me


O3 Cozmos







Edited by Captain Cozmos
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