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Showing results for tags 'assembly'.
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So, as I've mentioned before, I've recently come back to Atari 8 bit computing after decades away. Currently I don't actually have any of my old hardware, other than 520ST. I am in the progress of procuring some old hardware in the form of an 800XL and supporting hardware(possible disk drives/SIO solution/display/etc). One of the goals I have set for myself is to *finally* do some programming for the old 800XL. I did BASIC back in the day on my old 400/800XL, when I was a kid. Then didn't really touch computing from 90-96 or so while I was in the US Navy. After leaving the navy I went to school and became a software engineer, which I still am today. But I never have done any assembly programming. Until I have actual hardware to develop on, I plan on using one of the emulators I've used over the years(most likely Altirra) to write/test my code. I'm also considering using a windows editor/compiler for the actual development work, whether I have actual hardware or not. Does anyone have any thoughts on how they would proceed if they were me? More later...
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Here's the 6502 assembler I mentioned recently on the Atari 8-bit forum. The reasons to write this were: 1.) None of the assemblers I tried could generate correct code for code assembled to run in zero page and have forward references to other code in zero page, changing their operand in real-time. 2.) I wanted to write an assembler in sh (years ago, I came across osimplay, which I thought was pretty neat). shasm65 is written in sh, the Unix Bourne Shell, with a few extensions used which are not available in all sh incarnations. So far, I have adapted it to work with bash, zsh (~28% faster than bash) and mksh (ksh93, ~52% faster than bash). ash, dash, ksh (ksh88) and pdksh all fail to work, either because they lack array support or do not allow function names to start with a dot. Both issues could be "fixed", but that would make it slower and/or pollute the internal namespace, so I decided against it. Its syntax is different from all other 6502 assemblers, because an input file is treated as just another shell script, which is sourced by the assembler. Mnemonics are function calls and its arguments are the operands. Labels are defined by using the special function L and assembler directives are functions starting with a dot, like .org, .byte, .word, et cetera. Labels are referenced as shell variable names (ex. jmp $label). Numbers/memory locations can be specified in decimal, hexadecimal (ex. 0xfffe) or octal (ex. 0377). To fix the main reason for writing this assembler (see point 1. above), shasm65 uses different mnemonics for some addressing modes. For example, loading A from a zero-page location is lda.z. This way, the assembler knows immediately exactly how much storage an instruction requires. addressing modes: implied no suffix, ex. cli accu .a, ex. rol.a zp .z, ex. lda.z 0xfe zp,x .z, ex. adc.z 128,x zp,y .z, ex. stx.z 64,y (ind,x) .i [,x], ex. lda.i [23,x] (ind),y .i [],y, ex. cmp.i [017],y immediate ., ex. lda. 17 absolute no suffix, ex. dec 0x6ff absolute,x no suffix, ex. inc 0x0678,x absolute,y no suffix, ex. ldx $fubar,y (abs) .i, jmp.i [0xfffe] relative no suffix, ex. beq $loop directives: .org start [dest] start address of next block (optionally loaded at different location) .byte x y z ... include literal bytes (no comma but spaces between the arguments) .word x y z ... include literal 16-bit little-endian words .ascii "ascii string" include literal string .screen "string" include literal string of Antic screen codes .space size reserve size space .align b align to b-bytes boundary .binary filename include _raw_ binary file filename . include source file (shell script, library functions, etc.) L name define label Because both the assembler and the source files it assembles are just shell scripts, you have all of the shell functionality (including calling external applications) as your "macro" language. You can create your own functions, use for loops, tests, if/then/else/fi conditional assembly, arithmetic, all you can think of. # lines starting with a hash are comments # the code below demonstrates a few of the features START_ADDRESS=0x3000 clear_pages() { # start number_of_pages ldx. 0 txa L loop for foo in `seq $1 0x0100 $(($1+($2-1)*256))` ; do sta $foo,x done inx bne $loop } .org $START_ADDRESS L clear_some_mem # inline unrolled loop to clear 0x4000-0xbfff clear_pages 0x4000 $((0xc0-0x40)) rts L host_info .ascii $(uname -a) There are two built-in functions: lsb() least-significant byte, ex. lda. `lsb $dlist` msb() most-significant byte, ex. lda. `msb $handler` Variable-, function- and label names should not start with an underscore or a dot. Both are reserved for the assembler itself. Also, all shell reserved words are prohibited. shasm65 has the following command line options: -oFILE write output (Atari 8=bit $FF$FF binary format) to FILE -v verbose output -h -help --help -? output credits, license and command line options with a short description and their defaults So, why a shell script? Well, because I can, it is fun, the code is short (~300 lines), it runs on many, many platforms, it provides a very powerful scripting/macro language and it's fun So, no drawbacks? Yes, there are. Shell scripts are interpreted and therefore shasm65 is a lot slower than the usual assemblers written in C and compiled to native machine code. I have probably missed describing some features or quirks, but basically, this is it. Have fun Any questions, post below. shasm65-0.91.tar.gz
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In my ramblings with Level-2 and Level-3 I/O I found that, if a file is opened for Level-3 I/O, a Level-2 I/O call appears to fail. In a test program I open a DF128 file and read the contents. At EOF I close the file. The test program uses a copy of Tom Bentley's "TCIO" library that I disassembled and modified. I added two functions, 'tstat' and 'tstats' 'Tstat' uses the Level-3 STATUS (Op-code 9) command to get information about the test file. 'Tstats' uses the Level-2 Get-File-Info (0x14) command to get information. I was going to merge the two so I can get info to load a PAB for Level-3 access. Before and after each Level-3 TCIO call I use 'tstat' and 'tstats' to see how the information changes as the program performs the various library calls: Use 'tstat' to get file status (Level-3 Op-code 9). Print results and info. Use 'tstats' to get file information (Level-2 Op-code 0x14) Print results and info. Do a Level-3 operation. Get file status (Level-3 Op-code 9). Print results and info. [Repeat Step 1.] Get file status (Level-2 Op-code 0x14). Print results and info. [Repeat Step 2.] I found that Level-2 'Get File Info' command appears to fail with Error Code 7 (file error) if the file is opened for Level-3 access. After closing the file the Level-2 commands once again work. My merged file-info function will have to skip calling the Level-2 call if the file is open, but I do not see that being a problem. Also, I hate to say that my copy of Thierry Nouspikel's TI99-Pages has the 0x14 command returning the record-count at Result-pointer+8 as a byte value. Fred Kaal says this is a word value, and my experiments seem to indicate the record-count is a word. Both sites have been immensely useful for my experiments. K-R. -
I'm learning assembly, and in reading the Editor/Assembler manual for the DIVision statement, I was surprised to find that if the divisor and dividend are equal, DIV doesn't return 1 with remainder=0. It sets the overflow bit. I assume that the DIV statement works by repeated subtractions. So I would naively expect that, say, 5/5 would involve subtracting 5-5, incrementing the quotient to 1, and checking the remainder (0). Why does it cause an overflow, instead? (I don't know if this is really appropriate for the Development sub-forum, but I thought it might be because of getting into the nuts and bolts of the CPU. Apologies if it's in the wrong place.) Related: I have found an error in the E/A manual for the AB command that isn't listed in the Erratum. Is anybody compiling a list of additional E/A manual errata here? -
Hi, all, I'm practicing assembly language with the Editor/Assembler, using the xdt99 cross-assembler with Emacs on a Mac and running it on js99er.net for the emulator. So far, everything has gone very smoothly...but this one weird bug: If I have a period in a TEXT directive string, I get unpredictable VDP results when I display it using VMBW. For example, I printed my name to the screen (along with some other text), with the text set as: MSG2 TEXT 'Timothy S. Hamilton' The other strings printed to the screen just fine with VMBW, but this one came up with the last byte displayed as a space: Timothy S. Hamilto Thinking I'd miscounted the bytes by one, I tried other combinations of characters. It turned out it was the period causing the problem. Later, after putting it back in, sending this same string to VMBW caused the screen to flash with colored noise. Another time, it made it go blank, with a solid color on the border. [Edit: It was another version of the string that caused the flashing, with one or two characters changed, but with the period still there. I haven't tried replicating that particular behavior since then.] I thought it might be some glitch in encoding the period, so I opened up my assembly source file in E/A directly and put the period in there. It displayed the period just fine. Does anybody have a suggestion as to what might be causing this and how to get around it?
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Hey everyone! It's been a while since I've worked on anything atari, but I've started up a new homebrew project that I hope to finish, tentatively called "Taxi Panic!". It's a top-down city arcade taxi game, I'm aiming for a city that's maybe 7x5 screens or so in size. You'll be picking up fares and delivering them to their destinations while the clock ticks down. Sort of a 2600 homage to Crazy Taxi. So far I've got a first pass at the driving physics and car sprites implemented, and now I'm working on designing the city layout. I'm trying hard to make the car physics feel as smooth and "analog" as possible, right now the movement works in 11.25 degree increments (32 directions), and the visual sprite has 16 increments (22.5 degree precision). movement values are based on a lookup table for sin/cos values times an acceleration curve for speeding up and slowing down. The city will be created entirely with the playfield, and I need each screen to line up properly, so in order to make designing it easier, I've decided to make myself a little tool: It's an app (made in Unity, since I'm familiar with it) that actually runs on my iPad, and lets me design the city easily. Eventually this data will be exported out of the app into playfield data for the game. Anyway, I'm starting this thread because getting feedback tends to keep me motivated. Let me know what you think!
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I'm using my HDR ramdisk a lot while developing my TiVi editor. It's a real time saver. It's especially helpful when dealing with large files (which is kinda my primary purpose why I started working on TiVi). Today I read the updated documenation the InsaneMultitasker provided as draft. In there I learned that with ROS it's possible to use data buffers that reside in CPU RAM insead of VDP RAM. That is something I really want to try, because even with a RAMDISK reading a large file (think >100 kilobytes) takes some time. Now my challenge is; How can I easily detect from assembly language if I'm dealing with a "high-speed" disk device compared to a "slow" disk device ("floppy"). With a high-speed device I mean: CF7+, Nanopeb TIPI HDR ... I see differents possible paths here: CRC checksum on DSR space (but won't work with RAMBOS? Self modifiying code, configuration stored here too?) Check on some specific device feature? Actually I think that the CRC checksum logic would work quite well (I already did a test program on that about a year ago), but I'm not sure about HDR. Thinking about it would be cool if there is some unified way to detect device capabilities accross devices. For example a standard where there's a device "capabilities" file that is automatically created when the device is formatted. That file could then be processed from TI-Basic, assembly language or any other language supporting file I/O. Any ideas? -
I'm declaring R3 to be the final version. (This is my first post, but I've been lurking for a few weeks while writing this game, and I've really enjoyed trying out other homebrews.) Water Diver is a reflex game, for one or two players (simultaneously): dots are bouncing everywhere in the water; collect the good ones, while avoiding the bad ones! Five Six Twelve exciting levels, four exciting songs. ? No title screen yet... The graphics are pretty simple, but I think it's fun, and challenging. I have yet to break 150 points, except when testing at slow emulation speeds. There can be a lot going on onscreen. My high score during development is 162; for R3 as released, my best so far is 131. Latest release: water_diver_R3.bin (NTSC) water_diverpal_R3.bin (PAL60) Older releases: water_diver_R2.bin (NTSC) water_diverpal_R2.bin (PAL60) water_diver.bin (NTSC) water_diverpal.bin (PAL60) I've tested in Stella 6.0.1, and on an NTSC 2600. In Stella, it's difficult with keyboard, but I find that it works quite well with a mouse. The two-player mode hasn't had a lot of play; please let me know what you think! Also feel free to suggest PAL color tweaks, or whatever else. I have a very small amount of room left. I expect to at least add a few more levels. Or maybe a title screen. Controls: Joysticks. Either player can start at any time, by pressing their fire button; after that, just steer the button will give a lateral speed boost. Between games, you can cycle through game modes, with Select: In the default mode, you advance from level to level in time with the music. In "flow mode" you stay on one level forever -- any level you have reached previously. (This is more fun than it sounds!) Hints: There's no way to only one level where you can restore your health. You can see how much damage you've accumulated by looking at your score. The faster you pick up the good dots, the sooner new ones can appear. (It can be dangerous to pay too much attention to this fact.) When the water turns green, watch out... The game is inspired by https://www.khanacademy.org/computer-programming/water-diver-sounds-added/5430351862169600
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On the Atari 8-Bit Forum, Heaven/TQA asked for help with retrieving an ASCII version of his demo sources in Macro-Assembler XE format. Because I recently wrote a detokenizer for Mac/65, I thought it'd be fun to try this file format too. Here's the result. It successfully detokenizes all the sample .ASM files I found in his zip-file, but I'm sure some functionality is missing (at least three assembler directives). If you stumble upon files that fail, please send them to me and I'll update the detokenizer. Or send me the Macro-Assembler XE manual, so I can add all directives at once. Compile with: gcc -O3 -std=c99 -W -Wall -o demaxe demaxe.c Run with: ./demaxe fubar.asm > fubar.txt Should also work under cygwin/mingw32. If there's interest in a Windows-binary, I might setup a cross-compiler. Leave a message below demaxe.c.gz
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While I was browsing some old source code, I frequently stumbled upon MAC/65 tokenized files. Being too lazy to repeatedly start an emulator to convert them to (AT)ASCII and being unable to find a program online to detokenize them, I set out to write such a program myself. With some luck, I found a description of the format in the form of an old Analog Computing article. After that, it was pretty straightforward. Here's the source. Compile with gcc -W -Wall -O3 -o demac65 demac65.c. If you want line numbers, uncomment the printf statement. If you want all lowercase, there's tr(1). Have fun demac65.c.gz
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Two months ago I found a SID disassembler at the website of Covert BitOps. I rewrote large parts of it and added support for SAP and NSF (NES) files. It tries to do some simple code-flow analysis to determine code and data blocks. The output is compatible with ATASM. Because I want to avoid it'll bitrot on my harddisk, like so many other of my projects, I decided to post it here. Have fun. Possible improvements (todo-list): * command line option to manually mark blocks as code or data * add emulation engine to better handle self-modifying code * multiple assembly formats (xasm, mads, et cetera) siddasm2.c.gz
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I am pleased to announce the release of my first Atari 2600 game programmed in assembly language. The game is called Gene Medic and it is based on a future of genome editing to cure common diseases. There is educational value to the game as it introduces concepts such as context-dependent mutations and the electronic health record. The full details along with the binary and heavily commented source code can be found at http://genemedic.org. Many thanks to everyone who has contributed to this forum. I learned a lot from this group and am, of course, still learning! I hope others will find my source code useful for their own Atari 2600 programming efforts.
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Hi, By swapping charactersets (as shown by Synthpopolooza) you can very quickly swap an entire set of characters each frame using memory pointers. So currently if you wanted to animate a single char with say 8 different frames you can setup screen ram, then do a memset with the next character index and thus create an animated char (even a full background). One of the great examples of what I'm thinking is Delta on the c64 - the animated starfield was pretty much a range of characters cycling to move the stars across the screen. Now we get to the fun bit. Can you configure something in memory (such as a small characterset) and update a pointer to cycle a character to animate a char on-screen? I certainly believe this could be the most efficient way to do something like this... So the question is can this be done??
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Hi again, Did a bit of restructuring and now it seems to go to the correct bank on power up. The issue I think is right after that it jumps into no man's land a.k.a RAM and never returns which results in a black screen with a brown messed up playfield and a horrible death sound. ? The strange part is bank 0 is so small it is latterly only a few bytes in size with only a few calls to the required syncing subroutine, and then the title screen kernel which draws the title screen using the playfield and yes all the graphics are in the same bank. Links Source Listing Binary
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In the April 1984 issue of Compute! is a favorite type-in game called Worm of Bemer. It was largely written in basic, and is a great example of a basic action game. The author challenged readers to improve upon the game, and I do not know how many times this has already been done, but my son and I are taking the challenge! The author Stephen Fultz said "Some features you might add include a routine to save the high score to disk, adding more players, or having Nerm go to a different room depending on which exit he takes. " Now - I'm telling everyone about the WIP, because I just love hearing all the news about other works in progerss, and I hope everyone enjoys various updates around this game as well. Also, so that this doesn't become a never ending project, the feature list is set in stone. We are taking Stephens challenge by adding these features: 1. Save high score to disk 2. Two player mode 3. Different exits lead to different room PLUS: 4. Rewriting in C/Assembly 5. 2 player mode will be competitive or cooperative 6. And re-doing the graphics, including new welcome screen and animated snakes. There is always the possibility that the game never finishes, but I have a good feeling about this one.... be setting out the goals, in public no less, I will not let feature creep cause this to never finish....lol This weeks task, is to re-do the Welcome screen. Here is the original One thing we could do is change the fonts only - and leave it at that, here is a new font: And lastly, we could try to put an image on the screen - or do that and the fonts also, here is a mockup of placing an image:
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Hi, I want to know what you guys think about the current title screen layout. Out of 5, 1 being terrible and 5 being excellent vote in the poll above and let me know what you think. I know it's basic with a single color but, I'm not good at making insane title screens like you guys. Also this is must a rough draft then the final build. I may add colors latter.
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Hi, Quick question, right now I have a 8k game using the standard F8 bankswitching scheme. Say I wanted to upgrade it to a 16k game via F6, how would I go about doing that? Do I just add the extra needed banks or is there a more precise procedure required?
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I am using this bit of code to decide if the velocity is going to be positive or negative when a new game is started. GetRandomByte lda Random asl eor Random asl eor Random asl asl eor Random asl rol Random ; performs a series of shifts and bit operations rts jsr GetRandomByte ; generate a random number lda #%10000000 ; 1 in most significant bit mean greater then 127 bit Random ; was it less then 127? bne RandomVX ; if it was then branch lda #$ff ; set the starting duck's x velocity to -1 jmp RandomVXDone ; and jump cause we're done RandomVX lda #$01 ; set the starting duck's x velocity to 1 RandomVXDone sta DuckVX ; store duck's initial x velocity jsr GetRandomByte ; generate a random number lda #%10000000 ; 1 in most significant bit mean greater then 127 bit Random ; was it less then 127? bne RandomVY ; if it was then branch lda #$ff ; set the starting duck's x velocity to -1 jmp RandomVYDone ; and jump cause we're done RandomVY lda #$01 ; set the starting duck's x velocity to 1 RandomVYDone sta DuckVY ; store duck's initial y velocity However no matter what the velocity always stays the same. Bin: https://www.dropbox.com/s/ikjnebg1moyn0k4/duckgame.bin?dl=1
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I know that the 2600's RAM and stack are in an unknown state when first turned on and that's why we clear the RAM and setup the start immediately. I was wondering if there are any registers that still are in an unknown state after clearing the RAM and setup the stack. I ask cause I would like to use that to seed my random number generator function. -
I am having a small issue with my code. I am trying to get the duck to stop when it reaches the top after hitting the flyaway state. However no matter what I try the code gets ignored. Source Code Relevant section Any of you experts have any ideas on what's going on?
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[Make sure you download the files attached to this post, as they are the most recent. I only have permission to edit this post.] Hello, everyone! I've been developing an Atari 2600 homebrew game for the last little while, and I think it's nearing completion, but I'd like to get more feedback before I call it final. It's a 4K, single player paddle game with SaveKey/AtariVox support. Plot: In this game, you must use the paddle controllers to steer your car left and right, avoiding obstacles in your path while collecting treasures. When you touch a treasure, you will get 1500 points and it will be added to your collection (the yellow dots on the left side of the status bar). You can have up to 5 treasures in your collection at a time. At any point, you can press the paddle controller's trigger to "burn" a treasure, giving you the energy to jump a short distance over any obstacles in your path. Any treasures you have left when your game ends will grant you an extra 1500 points. The game is won upon reaching 99,999 points. There are different kinds of treasures. Some of them will grant you unique powers: Gold coin: Does not grant any powers, is only worth points. Necklace: Gives you an extra life (the red dots on the right side of the status bar). You can have up to four lives at a time. Jar: Lets you pass through all barriers for a few seconds. Statuette: Lets you jump as much as you want with no penalties for a few seconds. The game will speed up when you get enough points. There will be a transition period where the game stops generating obstacles briefly, and the speed-up will occur while there are no obstacles on the screen. The difficulty switches toggle certain features. I highly recommend setting both to A for the full experience (Note: Stella sets both to B by default): - The left difficulty switch will make obstacles farther apart (B) or closer together (A). - The right difficulty switch turns moving obstacles off (B) or on (A). If the game feels too easy for you, enable Speed Freak mode! Simply press the game select switch at any point. When the title screen's background is red, this mode is enabled. Finally, the most important feature: if you press the paddle trigger while you have no treasures in your collection, you can honk the horn! Wow! As previously mentioned, the SaveKey and AtariVox are fully compatible for saving high scores (although there are no AtariVox speech functions). It saves unique high scores for Normal and Speed Freak modes. If you want to clear your high scores, press the game select and game reset switches at the same time. So, that's everything you need to know! Feel free to give feedback. However, there is very little free space in the ROM, so I probably won't be able to implement any extensive new features. Sorry about that. [Please make sure you download the following files] Drive! v1.5.3 NTSC.bin Drive! v1.5.3 PAL.bin
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I adapted a self-modifying 48-pixel routine from JAC!'s Silly Venture 2017 Invitro for a little personal project, and for some reason the address of one of the immediate operands in the routine, 4thColumn, is being treated as an absolute address instead of zero-page, even when zero-page addressing is specified with the .z suffix applied to a STA. Could someone help me figure out why DASM is running into this issue? I'm running version 2.20.11 on Windows. Here is the listing for my RAM declarations so far: 10 U0000 ???? seg.u RAM 11 U0080 org $80 12 U0080 13 U0080 00 00 00 00*ramDraw ds 52 ;buffer for self-modifying code 14 U0080 00 81 loadIndex equ ramDraw + 1 ;immediate operand, init'ed before draw 15 U0080 00 8f colorTable equ ramDraw + 15 ;bottom of sliding color window, init'ed during vblank 16 U0080 00 a6 4thColumn equ ramDraw + 38 ;immediate operand, set in media res 17 U00b4 00 temp ds 1 18 U00b5 00 00 bgPtr ds 2 19 U00b7 00 gfxHeight ds 1 Here are all the store instructions that I will use in relation to the self-modifying kernel (to be clear, I wish to avoid needing to use the .z suffix). I see that DASM isn't initializing the 4thColumn address. 124 f8ab 85 81 sta loadIndex 125 f8ad 85 8f sta colorTable 126 f8af 85 90 sta colorTable+1 C:\Users\galen\Desktop\vcsdev\big_mood.asm (127): error: Syntax Error '4thColumn'. 127 f8b1 8d 00 00 sta 4thColumn C:\Users\galen\Desktop\vcsdev\big_mood.asm (128): error: Syntax Error '4thColumn'. 128 f8b4 8d 00 00 sta.z 4thColumn And here is the issue exhibited in context: 99 f876 ramDrawTemplate 100 f876 a0 00 ldy #00 ;02 , 63:189 (loadIndex @ +1) 101 f878 b9 00 00 lda gfx0,y ;04 , 67 102 f87b 85 1b sta GRP0 ;03 , 70 103 f87d 85 02 sta WSYNC ;!0 104 f87f b9 00 00 lda gfx1,y ;04 , 04 105 f882 85 1c sta GRP1 ;03 , 07 106 f884 b9 00 00 lda clrTab,y ;04 , 11:033 (colorTable @ +15) 107 f887 8d 08 01 sta $100+COLUPF ;04 , 15 108 f88a b9 00 00 lda gfx2,y ;04 , 19 109 f88d 85 1b sta GRP0 ;03 , 22 110 f88f b9 00 00 lda gfx3,y ;04 , 26 C:\Users\galen\Desktop\vcsdev\big_mood.asm (111): error: Syntax Error '4thColumn'. 111 f892 8d 00 00 sta.z 4thColumn ;03 , 29 112 f895 be 00 00 ldx gfx4,y ;04 , 33 113 f898 b9 00 00 lda gfx5,y ;04 , 37 114 f89b a8 tay ;02 , 39 115 f89c a9 00 lda #00 ;02 , 41:123 (4thColumn @ +38) 116 f89e 85 1c sta GRP1 ;03 , 44 117 f8a0 86 1b stx GRP0 ;03 , 47 118 f8a2 84 1c sty GRP1 ;03 , 50 119 f8a4 84 1b sty GRP0 ;03 , 53 120 f8a6 c6 81 dec loadIndex ;05 , 58 121 f8a8 d0 cc bne ramDrawTemplate ;*2 , 60/61 122 f8aa 60 rts ;06 , 66:198 - 52 bytes The graphics and color addresses are uninitialized because I haven't written those tables yet. I just need to get past this stumbling block in the immediate operand.- 4 replies
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Heroes & Shadows Website: https://heroesandshadowsgame.neocities.org Screenshot Story An alien Xolan has crash landed on your planet to warn you of the Mavok an evil race of creatures that want to enslave all. The creature isn't strong enough to fight them and needs your help. Help him become the strongest creature in the universe! Objectives To grow your pet to become the strongest. Controls Left Joystick Up/Down: Select Command Fire: Use the selected icon Right Joystick Atarivox for saving progress and voice speech (Optional) Builds Latest https://www.dropbox.com/s/auqkkwoecu6bvn9/has.bin?dl=1
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On March 26, 2018, I posted the following message to the BallyAlley Yahoo group: Is anyone interested in having a programming contest for the Astrocade? My ideas: 1) Program in machine language or BASIC 2) Short programs for a start 3) Program of any kind (game, demo, music, video art, etc). 4) Prize? I've no idea. Does anyone want to give this a go? Adam ----------------- David Dibbern responded with: My skills were fair back in The day, but I would be interested in a retro port contest. A contest to make any retro arcade game that was not already done for the Bally, ported over . I would even pay pal $10 for starting a prize fund for this. We could get some cool retro games that we wanted to see ported but didn’t ever make it to the Astrocade Thanks- Dave ----------------- Thomas Burtell said: This would be very interesting! Programming has changed so much over the years and we all have gotten better. I'm focusing on other stuff right now, but I'd definitely like to see this Bally-battle. It's like what they do on StackExchange with "Code Golf". You have to write the tightest code with the minimal of resources. ... back to lurking. ----------------- Is anyone here on AtariAge interested in a programming contest for the Astrocade, either in BASIC or machine language? Adam
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I am trying to get my "character" to bounce between the left and right parts of the screen. Here is the code I'm using: First, the global equates: LEFTBOUNDRY equ #20 RIGHTBOUNDRY equ #144 and then the actual code: ; pet movement code lda PetX ; load pet x position into accumulator clc ; clear carry flag adc PetVX ; add the pet's velocity constant sta PetX ; store pet's new x position cmp #LEFTBOUNDRY ; does it intersect the left boundry? bcs SkipReversePetDirection ; if not branch cmp #RIGHTBOUNDRY ; does it intersect the right boundry? bcc SkipReversePetDirection ; if not branch lda PetVX ; load the pet's x velocity eor #$ff ; negate it adc PetVX ; add pet's current velocity sta PetVX ; store the pet's new velocity SkipReversePetDirection Also here is a link to the full source code: https://www.dropbox.com/s/6g6fmpmksvx7dmo/Source_11-14-18.zip?dl=0 Thanks for the support so far, Heroes & Shadows
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