Alex H

Hi Folks, it's about time I posted an update. Unfortunately I haven't made much progress with MGD over the past year or so. I've had some heath problems to contend with (including a brain haemorrhage - ouch!!!), and it's hard to get back into a project when it's been left so long. Anyhow, the latest binary is here. The level data is still far from complete, I still have more speech to add and other little bits to do here and there. I've put in some title screen music (known bug: music goes crazy when you reset out of the game). And I've updated the scoring system (the number of points scored for each platform passed increases depending on which fruit you're on). I'm sure there were other changes but I can't remember off-hand. Hopefully I'll get this finished sometime soon. Alex

; divide value in temp by 10 lda temp lsr lsr clc adc temp lsr clc adc temp lsr lsr lsr clc adc temp lsr clc adc temp lsr lsr lsr lsr sta temp I think that's right.

Here's another little scroller demo. Binary only this time until I get it cleaned up. I wrote this on a PAL machine (PAL60) and haven't sorted out NTSC colours yet. The background should be red/blue but will be purple/green in NTSC. Runs ok in Z26 (press the "-" key to switch to PAL colours) but Stella chokes on this with my 3GHz machine! pscroll.zip

So they make the bubble less evil? Each down arrow collected adds a very small amount to gravity, irrespective of what other power-ups you have. It's very subtle - you need lots of them before you really feel it, although even a small increase in gravity can make all the difference with the longer platforms. The later levels will be faster and it becomes increasingly difficult to not get pushed off the top of the screen, so extra gravity is worth having. Remember, this is a WIP so lots of things aren't quite perfect yet. I'll adjust things like the amount of gravity added once I do more thorough play testing. Well, reversing the controls I can deal with if I'm prepared. Depends where the mushroom is when I grab it. But I'll agree sometimes they can be deadly. The mushrooms give a good/bad trip depending on what colour they are. The bad trip is obvious, the good trip let's you miss fruit without starting back at the cherry plus a points bonus (not sure if that was in the last version I posted). I don't know that I've ever missed a gold cherry, but I know I often don't reach the cherry and yet still get the warp option. Probably because I have an Atarivox. At the end of each level is a golden fruit. Collect the gold fruit to enable teleport back to that level. Say you have collected 2 gold fruit, then you will see the teleport at the beginning. Jump through that and you will see a second teleport, etc. The number of opened teleports is stored in the AtariVox - this is basically how I've implemented the level select. The blue zone is the end of the test data - there is nothing (playable) beyond it in this version.

50/60 bytes/sec is fine for speech, not so good for the synth. I output the speech during overscan which has little else in it apart from sound. At one point I was testing the timer after sending a byte and if there's enough time, repeat. (Usually fitting in 3 bytes per frame.) But I couldn't hear the difference. With the longer speech strings it was filling the SpeakJet buffer anyway at a single byte per frame, so there seemed little advantage. The latency is pretty tiny unless there's a whole heap of control codes. The way I look at it, latency isn't a problem if the user can't/doesn't notice it. But I must admit, I haven't done much with the SpeakJet synth functions. I've only just started work on it again after being unwell recently. But I'm hoping to have a finished version (or nearly finished) for CGEUK on 13th Aug. So hopefully not too long after then.

I've not noticed that That's deliberate. I put a pause in the data so he burps a moment after eating the food. I also tend to put short pauses at the start of other speech strings in case one bit of speech interrupts another. (Not that that happens much in MGD.) I made a habbit of doing that after coding the Verzerk speech hack (Vectrex) where speech strings get interrupted more often. Just sounds better that way.

Like the title says. wscroll.zip

Yes, what was I thinking? And I was programming sound just an hour before writing that. Yep. I think the main reasons there isn't much in-game music on the 2600 is because it only has 2 channels, and developers wouldn't want to use up valuable ROM space on music that sounds nasty.

So if the TIA was "by all accounts" better than the sound chip of the spectrum, why did Atari use the speccys chip for the Atari ST instead of its own "superior" TIA? 900398[/snapback] The 48k Spectrum didn't even have a sound chip. It had a single I/O line connected to the speaker which was twiddled under CPU control. The Atari ST used the Yamaha version of the Intellivision (GI) sound chip. (The later 128K Spectrums used the GI sound chip, as did the Vectrex, MSX and others.) The TIA has more waveforms than the GI chip so is more flexible in the type of sounds it can make, but only has 2 channels and 8-bit pitch control. The GI sound chip has 3 square-wave oscillators with 12-bit pitch control which makes it more tuneful, plus a noise generator and envelope generator which can also be used as a triangle/sawtooth oscillator.

$351!

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewI...item=8205899912 I wonder how much it will fetch? This was the previous one sold on eBay: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewI...item=8193364813

Better on the CD than not at all. He's still making them, but as and when he has time. He only sells them on eBay when he has a batch made. No, sorry I don't. I'll ask around.

No problem! Hmm... The mag is sold for profit presumably, and it's the content (print and CD) which is where the value is and what people pay for. No print/CD, no sales. So, technically I would say it's a no no. The copyrights are still in effect - they're not PD. Also, some of the games were licenced from Cinematronics, Konami, Namco, etc., and there may be limits on how/where those titles can be published. So it's possible that Jay himself wouldn't be able to give permission. Having said that, Sean Kelly sells his multi-carts and some of the websites that have the ROMs for download carry advertising. But if I were in Martyn's shoes, I'd really want to speak to Jay Smith. Some of the homebrewers might be happy to have their ROM images on the CD? My stuff doesn't work in the current emulators so there's not much point. BTW, Jeroen received an email from Jeff Corsiglia and posted it to rec.games.vectrex. Here's a copy: (Hope that's ok Jeroen?) Perhaps Jeroen could put you in touch and he might be up for an interview for the mag?

Nice! I might have to make myself one of those.

Just been listening to some C64 remixes over at remix.kwed.org. I absolutely love Scroll Machine (5th Dream About Happiness) - LMan, even if it does sound a little like pr0n music. But can someone remind my what game the first tune in Sidology Episode 3 - machinae supremacy is from? I've got Bubble Bobble, Arkanoid, Monty on the Run, Commando and Out Run. Just can't place the first one.

Getting back on topic... There's a bunch of Vectrex reviews here. Apparently there will be more shortly. Personally, I think he underrates Scramble - how it can score lower than Starhawk I don't know. But hey, he rates my games pretty high so I shouldn't complain. BTW, Jeroen (owner of that site) sells some nice Vectrex T-shirts. Only the larger sizes left, but that should be ok for you fat bloaters!

Heh, you knows it! I'm really eager to do this, but it's an ambitious project and there are some hurdles to overcome. The sound is going to be tricky - the voice samples will need a lot of ROM space and there are technical issues with playing them and drawing stuff at the same time. Also, there can be a lot of objects on screen. The problem is not so much in displaying them but the collision detection between them all - that can chomp away at the available CPU time big time. There are ways to streamline this but that needs more RAM. So it all depends on how it goes with the cart design. (Looks good on paper.) It will also take a lot of time to program. Besides, I must finish Man Goes Down first and the VecLink game before I really get stuck into it, so don't expect it any time soon. I've had other *big ideas* before and had to scrap them for one reason or another. Aaargh! You shouldn't set me challenges like that! Yes that is a problem. Someone is working on Robotron though. Haven't heard anything in a while though so don't know what's happening with that. Right... it's been a while since I unlocked them.. Actually I thought it was related to the levels now that I think of it... I just shot down all the UFO's anyway... But other than the 7 extra modes, there's nothing to be unlocked, right? No, apart from being able to start at the higher levels, there's nothing more to unlock. Hmm, interesting idea. That wasn't possible because the Protector high score table takes up most of the EEPROM space. That would be nice. But even the simple Protector overlay was damned expensive to produce. I don't have one. The Scramble overlay works ok, but I have a Berzerk overlay on the screen most of the time when playing games that don't have overlays. I just love the way the screen looks in blue.

I don't know. Haven't tried. Originally we didn't have the Static Allocation Area, just 256 blocks of file system (so it could take twice as long when the file is in located last block). I asked people how they felt about the screen blanking - no one had noticed. Just a few frames, at a time when there was a screen transition anyway. BTW, did you notice the screen blank when the high scores are saved/loaded in MGD? Ok, it's quicker than a full search would be, but still, it's pretty unobtrusive. Ok, I misunderstood what you were saying there. But it's still more complicated and uses more resorces (ROM, RAM) than what people wanted. (Me included.) They are not. The AtariVox was designed pimarily for the 2600 which as you know only has 128 bytes RAM. So simplicity was chosen over the need for bigger files. If being used with say the 7800 and more than 117 bytes are required, then multiple files is the solution. Systems that would require bigger files have more resorces to cope with this, but yes it does make things more messy in this instance. There is the situation were one file of a set could be overwritten, and it would have to be down to those applications to deal with that. Not perfect I know, but the most important factor is that it must be as simple as possible for the 2600. From talking to people who actually wanted to use the file area, that would be too much. In the same way in which you'd need to let the user choose what they want to load. The ability to either overwrite or delete files is necessary to avoid having a separate memory manager cart. Sorry if I sounded rude - didn't mean to. A couple of people are already developing programs which will use the file area, and we've done our best to cater for their needs.

Yep, broken. It's probably fixable. If you hear sound, it's likely to be one of 3 chips that's gone bad. Often it's the 6522 (replace with a 6522A if you can find one - not all 6522 chips work properly in the Vectrex.) But the fact that you can see some lines radiating out of the spot suggests it might not be that though. It could be the MC1408 DAC (common cause for white-dot syndrome), or one of the op-amps (I forget which one). If you don't get any sound, it's almost certainly the 68A09 CPU that needs replacing. Search the rec.games.vectrex newsgroup for "white dot" - you might find some info there.

Sounds very promising being a great fan of shooters! Uhm... Use external ram and swop mem? 884138[/snapback] I'm trying to develop a mega-cart which has a nice big ROM and extra RAM, but that's for a different game - also a shooter (2D) and probably far cooler than XYLO. (I'm a fan of Williams arcade games - can you guess what it is yet? Still in the very early stages of development so I don't want to promise too much just yet.) Nothing is unlocked based on score so perhaps you've found them already?

If I might make a few suggestions, I've done some flash file system stuff and I really don't think the proposed file system is too good. You might be looking at an old document. This has already been thrashed out months ago on the Stella list and via many emails. Not a lot. Simple loop. The memory is quite small, searching is fast - it happens in the blink of an eye. I don't see a problem here. Hold it right there! No! There is no need for an memory manager cart. There is no need to put that additional cost on the end user. We do not want this. This would only be required if the file system can be corrupted to the point where it no longer works. That would be a bad file system for this application. Way too complicated for what we need. The format is: Each 128 byte block starts will 11 character filename (7 bit character codes), 3 char file type, 8 char filename. Bit 7 of ther first byte is 1 of the block is free, 0 if the block is in use. The remaining bytes in each block are for user data. ID bytes are a bad move since they are not human readable. A list of IDs needs to be maintained and it's more finite than what we already have. To make them human readable, any application which shows the directory would need to know the meaning of all IDs. What happens when new IDs are added? Does everyone have to send their memory manager cart or games back to be updated? Linked lists are bad because they are corruptable and can break the file system. BTW, What are the RAM requirements of your proposed system? This is something that is critical to those who are already working on projects which use the file system. How does the memory get formatted for use in the first place? The existing system does not require any formatting. A blank EEPROM (full of 1s) will just show all blocks empty. The page-write limit of the EEPROM pretty much prevents mass curruption of data. Any blocks that do get corrupted can just be overwritten/deleted by the application software. This shouldn't happen. Any program that uses the file system should be able to save data to any block, whether previously used or not. Simple. To be frank, no, sorry. I fail to see how it cures any problems, but it creates new ones. Search the Stella archives for "AtariVox EEPROM File Format" to see some of the talk about this.

Man Goes Down on the 2600, of course! My next Vectrex release will be the VecLink Maze game (still needs a title - Berzerk Arena perhaps?). Whilst it does have the single player mode, it really plays best with 2 linked Vecs, so it might have limited appeal. I plan to sell pairs of cartridges with VecLink cable. No fancy box or overlays this time. (Game is about 90% complete.) There's also that 3D shooter XYLO but I'm not sure what will happen with that. I'm very short on RAM and can't really fit everything in that I had planned. But maybe I'll do something with it - would be a shame to scrap it at this stage. I might bash out a mini-game too - Spike Goes Up. (If you've ever played Jumping Jack on the ZX Spectrum/Amstrad CPC or Leggit! on the Dragon 32, you'll get the picture.) Cool, great to get confirmation that the article will be published!

Yes, the sound effects are a little weak, especially the fire sound - very hard to reproduce on this chip. It's a look-a-like rather than an accurate translation. Did you unlock any of the extra game modes yet? Go UFO hunting to unlock more modes. Cheers! You should definitely check out John D's carts: www.classicgamecreations.com Birds of Prey (on Vecmania) is one of my favourites. It looks slightly old and less polished than some of the more recent games, but I still love this Phoenix clone. Wormhole (Vectopia) is another one I fire up quite regularly. (Like Gyruss.) Gravitrex is one of the best Vectrex homebrews. Since you like Thrust, you should definitely check this out. It's a slight shame it doesn't have the nice zooming effects of the arcade Gravitar, but it has a lot of gameplay - probably more depth than Thrust. The various versions of Patriots (Missile Command) on these carts are also worth playing. Yes, it's a really nice game. I find it very hard though. I love this version of Thrust too. I always found the controls to be a bit tricky on other versions and was never much of a fan of the game, but Ville did a great job here. A must have Vectrex game IMO. Wow, I didn't know about that - even more of a bargain! Yep, top bloke! Yes .. there's a new game coming out this fall. The Vectrex is averaging about two homebrews a year. Don't forget Nebula Commander and Revector by Craig Aker that were released recently. (Available from Mark Shaker: www.vectrexcarts.com)

Yes, I will be putting more speech in there. Yes, there's something wrong with Z26's I/O emulation. No such problems when running on the real hardware or in Stella.

A possible solution would be to build the memory into actual joysticks - a "memory stick" so to speak. The problem is compatibility with the AtariVox.