playsoft

It was 2011 when I discovered Crownland and I was in awe of all aspects of it. And yes, the music is great especially that first track which is so catchy. It had never occurred to me, nor had I ever heard of, the idea that when you have too many sprites to display horizontally you simply draw different ones each frame. When I figured out that's what Crownland was doing, I had to dig out the 8-bit and have a go at writing one myself. I could see that Crownland was drawing as much of each sprite as it could, but in mine I only draw a sprite if it is fully visible. I did that for no other reason other than simplicity and regarded Crownland as the more sophisticated approach. I'd seen the Ripper video before but did not realise it was by the same author. In the other demos it looks like he has gone that route too, so presumably opinion was that it's better to see no sprite at all rather than parts of it?

At the moment there are no plans to add another GTIA 10 level, but if we do then we can try ANTIC 4 underneath. The status area graphics were just thrown together quickly to have somewhere to put a score. I'm not sure what will end up here, but as the sprites do not pass over it using PMs to colour it would be my preferred option rather than a flicker mode. I can send you the font if you want to play around with it anyway, and it'll be easy enough to try out anything you come up with, but I don't want to add flicker.

Exploiting the full potential of the machine is really more Harvey's motivation. Obviously I want to make it as good as I can, but for me it was to see if I could write a sprite multiplexer like Crownland and now it's to see if I can write something to the same sort of standard. Crownland was what got me interested in the A8 again, I couldn't believe it when I first saw it. It is a hard question to answer because it started off as a 48K program, so memory was tight from the start. One example I can give you is that each level has always been comprised of two character sets. After a previous tidy up exercise I offered Harvey a third but he didn't want it. So you could say that more RAM would make no difference to how the levels look today but Harvey's choice may have been down to not wanting to change completed designs. From my point of view I've not yet had to throw anything out because of lack of RAM. There is quite a lot of bank switching going on, so putting more core code/data in RAM may free up the cpu to do some more work, but to what extent I don't know.

It may make it in there somewhere. I did extract it and the robot a while back. I managed to get the robot into a character set quite easily but the mother ship will need some (a lot) of work. That was for putting it in a standard level though, I suppose if it is a special level then things could be done differently. So it's a possibility, although the end level seems far off in the future at the moment!

Yes, the final version will run in 16K too. That came about when we decided to go the Maxflash cart route. On one hand less people will run it on real h/w because they'll need a cart, but by making it run in 16K makes it of interest to 400/600XL owners too. As it turned out that was a good decision as it meant a 5200 version was possible with minimal effort (the 5200 only has 16K RAM). The only annoying thing is that before deciding to go the cart route I had a 16K 400 which I upgraded to 48K as that's what we were originally targeting!

Sorry, I should have explained a bit about the Maxflash cart files. They are in ab_maxflash.zip and there are 3 files: ab.bin is the raw cartridge image that you'll use with Maxflash Cartridge Studio to flash a real cart with the Maxflash Cartridge Programmer ab.car is the above image with a cartridge header added --- use this with an emulator as it saves having to select the cartridge type ab.atr is the ATR programming image which you'll use to program a real cart if you do not have a Maxflash Cartridge Programmer The Maxflash cart version will run on a 16K machine.

I would like to thank everyone who has provided feedback, without which there wouldn't be 5200 or RAMBO 1088 versions. There probably wouldn't be any background interaction either without the number of people who voiced it was needed. The rest of this year will probably be spent doing some tidy up and more foundation work. Next year it will be to try and make something playable out of it. I feel a little daunted to try and match in playability what Harvey has achieved with the graphics but I will give it my best shot.

There is a new demo available here: http://atariage.com/forums/blog/573/entry-11165-atari-blast-demo-july-2014/ Andreas: I managed to use Superpacker/Exomizer to make a smaller .xex file (I'm not 100% sure I did it right, but it seems to work ok on Altirra) but I don't know what you did to make an ATR.

There's a new demo available here: http://atariage.com/forums/blog/573/entry-11165-atari-blast-demo-july-2014/

Hi Al, Glad it worked! I'd used diagnostics mode because there was data at the end of the cart which I did not want to disturb so it bypasses the BIOS which would normally do these things (clear RAM & h/w). Paul

In this one I've cleared down all the hardware locations too... if this doesn't work I am out of ideas! Paul oil_fixed_3.bin

It's uninitialized RAM. You don't see the issue on an Atarimax since the loader will clear memory. You don't see it on Altirra either... unless you select Debug -> Options -> Randomize Memory At Cold Reset. I've cleared down memory during the initial boot and that now runs in Altirra with the above option selected, so hopefully it'll work on your cart now. Paul oil_fixed_2.bin

An untested one, also missing one of the paper roll spindles, sold for £51 on ebay in the UK recently: http://www.ebay.co.uk/itm/Atari-822-Printer-for-Atari-400-800-XL-XE-Computer-Systems-/131222990032?pt=UK_VintageComputing_RL&hash=item1e8d7fecd0 Let me know if you'd consider shipping to the UK as since returning to the Atari 8-bit I have wanted one, although I am not sure why. I am not a collector and can't see myself printing much with it, but I suppose it's because I used to have one back in the day and have fond memories of using it.

I'm disappointed not to see the dancing girls animated as I found them the most recognisable of all the images. It would have been interesting to see if fluid animation lessened the impact of the coarse resolution. Although no game was released, I don't think it was a complete fabrication. It looks like Pete has a software graphics mode working, has written an editor/converter for it, has sprite routines partially working and has put together all those background images. So some development effort has been spent to get this far. Under normal circumstances there would be more positive responses but unfortunately the bravado sales pitch backfired.

Referencing your disassembly and playing around with Altirra, the number of buckets is stored at $90. So if you modify: B937 DEC $90 B939 BNE LB947 To: B937 JMP LB947 B93A NOP Then you should never lose a bucket. Also the x positions of the bombs are stored at $A4..$AB and the bucket at $89 so you could do something like the attached... silly.bin

Could be that the controller pot inside the machine was mistakenly adjusted instead of the colour one since they are close together. I'm sure there's a post on here somewhere explaining how to adjust it but I couldn't find it - found a youtube video though: http://www.youtube.com/watch?v=NoaiF-xqzEg

There seem to be quite a lot of them! If based on the original cart then they should all fix up in the same fashion - I'll take a look later in the week. Paul

It's not an uninitialized variable, it is the PP joystick detection code: 6011: A9 00 LDA #$00 6013: 8D 1F C0 STA CONSOL 6016: A5 11 LDA $11 6018: C9 E4 CMP #$E4 601A: F0 04 BEQ $6020 It's disabling the joystick and expecting to read back a POT0 value of $E4 if one is connected (or rather a track ball is not connected). That logic is correct, what's wrong is that the shadow POT0 location ($11) is not updated until the next vertical blank. So rather than reading the POT0 value with the joystick disabled, it is reading the POT0 value from whatever the previous state was. When I tried it on my Atarimax Ultimate SD I did not initially see the problem. Only after I enabled the "Game Quick Start (bypass BIOS)" option (from the * key menu) did it occur. So that is one thing to try, disable the Quick Start option if you want to run the original ROM. If you've already tried that and it didn't work perhaps you have older Atarimax firmware. My version numbers are: hardware version 20110115 bootflash version 20110115 menu version 20110115 firmware version 20130504 I added a bit of extra start up code to disable the joystick and wait a few vertical blanks. This means the shadow POT0 location already contains the disabled value by the time it gets to the dodgy detection code. This was ok on my Atarimax with Quick Start enabled. pole.bin

My guess is it's an uninitialized variable, i.e. PP has a variable which it sets when it's detected a track ball - but it's not initialising it. It gets away with it on the real cart, where RAM will contain whatever it's power up value is, plus whatever the BIOS writes. Running via Atarimax RAM will contain data that was used for the menu, the loader etc...

You're most welcome. I never imagined I'd be coding on the 8-bit again and to my regret I had not kept anything from back then, so it was nice to find the source code on the issue disk.

Well, this is just a 20-odd year old magazine game, but it was interesting to be able to position the crosshair directly from the controller pots which I was expecting to be too sensitive. When you get your Atarimax SD please try out the ATARI BLAST! demo as this is the on-going project and more exciting (to me) than the old magazine stuff (although I still have one of those left to convert).

I think by default Altirra uses the left shift key as the upper fire button - and there was a bug in the initial Rampage conversion where that was configured to cause a break key interrupt without the vector being set. I think that is what you are seeing here. In the initial conversion there was also an issue with you getting stuck if you jump off left or right and end up at the edge of the screen. I've just tried this version and that bug is present too. So it looks like this version was based off the initial Rampage conversion and not the final one Wrathchild released here: http://atariage.com/forums/topic/223049-rampage-conversion/?p=2945929

This is another of my old magazine games, STAR RIDER, from Page 6 issue #36. Unbeknown to me until about 6 months ago, was that it was also published in A.N.A.L.O.G. issue #69 which I assume must have been an exchange deal between the two magazines. I can't say this filled me with joy since A.N.A.L.O.G. never paid out the prize money for the 1986 ST programming competition. However they did publish the source code on an issue disk which means I've been able to do this conversion using the original source instead of a disassembly (although my younger self didn't comment the code very well, it might as well have been a disassembly). This is a single chip 16K ROM image and uses analog controls by default. If you want to play it with a digital controller (or the standard controller in digital mode) you can press * to toggle between analog and digital mode. Below is what it looked like in the magazine but with the controls altered for the 5200. STAR RIDER Admit it! Paul Lay's latest space shoot out is just too fast for you - you are doomed! Your planet is being attacked by hordes of alien space craft and it seems you are the last hope of survival. You sit behind the controls of a Surface Runner vehicle which glides over the surface of the planet at an incredible speed. You are protected by a force field and armed with a limitless supply of photon missiles. You are the STAR RIDER. The object is to blast as many of the alien spacecraft as you can, without letting them get past you. Every time you hit an alien your score is increased and your shields are boosted, however when an alien gets past you it zaps your shields making your Surface Runner vehicle shudder. The game is over when your shields have gone. You will find STAR RIDER fast and furious especially at the higher levels, if you ever get that far! STAR RIDER CONTROLS START begins a game at wave 1 1, 2, 3, 4, 5 begin a game at levels 10, 20, 30, 40, 50 respectively # begins a game continuing from the previous level * toggles between analog and digital joystick control RESET aborts the game PAUSE pauses/resumes a game Use a joystick in port 1 to manoeuvre the crosshair sights and press the trigger to fire a photon missile. HIGH SCORES If you manage to survive that far, you will be able to enter your name on the high score screen. Moving the joystick left and right will move the cursor in the appropriate direction and moving the joystick up and down moves forwards and backwards through the characters. When your name is complete, press the trigger and your name will be entered. On subsequent high scores, the name entered appears as a default to save you entering your name each time. starrider.bin star_source.zip

Thetris does not work under emulation with the 2-port bios that Mitch posted because it copies the bios vectors from the wrong location. In that 2-port bios the vectors are stored at $FEAB and copied to $200. In my 4-port bios the vectors are stored at $FE95 and copied to $200. Thetris bypasses the bios initialisation and copies the vectors itself, but always from $FE95 to $200 even when using that 2-port bios. If I hack thetris.bin to change that location, it works with that 2-port bios. However, that it works on the two 2-port systems you have tested makes me think that either (a) they both have a 4-port bios fitted or (b) there is more than one version of the 2-port bios. Attached is a hybrid cart image for the Atarimax Ultimate SD which saves a copy of your bios to the SD card - it writes it to file bios.dat (unless you have cartridge services disabled in which case it will timeout and report an error). Also attached is my 4-port bios. If you save the bios from one of those 2-port systems, do they match the 2-port bios Mitch posted or my 4-port bios? Or neither? bios.zip biossave.zip

I use a 75W one: http://www.amazon.co.uk/gp/product/B004ZWHB56/ref=oh_details_o08_s00_i00?ie=UTF8&psc=1