EricBall

I have a dream of someday managing to convince my wife to let me buy a classic arcade game. One I think I would enjoy is Gauntlet. But, it would have to live downstairs, and I don't know if it would fit. Does anyone here have a Gauntlet they could measure (width & depth)?

See Announcing Skeleton+ for Albert's answer.

See above for an update to Skeleton+

Once I made the decision to create Skeleton+, I asked AtariAge to suspend sales of the original Skeleton. (Though they may have some still in stock if you ask nicely.) And I know I said previously would be the final version, but Paul Slocum has managed to persuade/encourage me to make one final enhancement.

Does anyone know how holey DMA mixes with indirect sprites? Do both the character map and the character sprites have to be on even blocks, or can either be on an odd block?

Thanks for the feedback Eckhard. I think it crashes after 15 minutes or more, when the tile list goes over the page boundary. This is my first attempt at a 7800 game/demo, and I'm flying by emulator only, so I'm not surprised that there are a few quirks. I'll check out your example program. Currently the DLL generates 192 active lines, with some top and bottom boundary lines. I'll check the border control bit. Maybe the sense is reversed from the documentation I have (Character Width was, at least). Something emulators don't show. My next challenge is to work on vertical scrolling, which means messing with DLL offsets and charbase for the top and bottom zones. More work for the NMI routine.

I've created the following demo for the 7800. It may form the basis for a game, but right now it's just an experiment to figure out how to do 4-way scrolling backgrounds on the 7800. The demo currently shows some blocky clouds drifting over a fixed blocky landscape. (Use your imagination.) Both are done using character maps (tiles). Although it runs fine via emulation, it may be more than MARIA can do in 456 cycles. I also haven't implemented wrap-around yet, so you may see some discontinuities, and it might crash or black out if left running long enough. The file is 8K and signed, so simply strip the 128 byte A78 header if you want to burn it to an EEPROM. 78scroll.zip

I've done one final tweak (see Final Skeleton+ so in a week or so AtariAge and PackRat VideoGames should be able to offer cartridges. Although the difficulty switches aren't the most intuitive way to select game options, they are very easy from a code perspective and very space efficient.

One last tweak and, barring any bug reports, this will be the final version of Skeleton+. TV TYPE SWITCH When the TV TYPE switch is set to B/W the Skeletons have the touch of death. The game is over if you are touched by or touch a Skeleton. Other topics: Announcing Skeleton+ Skeleton+ Rants Enhanced Skeleton+ May 14th - as I mentioned below, Paul Slocum made me an offer I couldn't refuse. This version shows the score on the end screen. skelplus.zip

The major limitation of the TIA sound generator is it only has a 5 bit frequency divisor. This really limits the number (and accuracy) of notes it can produce. But, it is possible to make decent original music and sound effects with the TIA. POKEY (potentiometer & keyboard processor) was created for the Atari 8 bit computers as a keyboard & paddle interface. It contains an improved version of the TIA sound generator with 4 channels each with an 8 bit divisor (versus 3 channels with 5 bit divisors) and pairs of channels could be linked to create a 16 bit divisor. This provides the required resolution for accurate notes, and thus decent music reproduction. (Though still with fairly limitted 1 bit polynomial waveforms.)

Based upon the feedback provided, I have enahnced Skeleton+ to provide greater variation and difficulty. From the manual: DIFFICULTY SWITCHES When the LEFT DIFFICULTY switch is set to A when the game is started, you will need to destroy ten instead of five Skeletons to complete each level. When the RIGHT DIFFICULTY switch is set to A when the game is started, you will start with 49 life instead of 99 and your Undead Disintegrator will only do half the damage it does when the RIGHT DIFFICULTY switch is set to B. When the LEFT DIFFICULTY switch is set to A during the game your Undead Locator is turned off and you must use sound to find the Skeleton. Stereo sound is recommended in this case. When the RIGHT DIFFICULTY switch is set to A during the game the speed of the Skeleton is reset only at the start of each level. See also Announcing Skeleton+ and Skeleton+ Rants. skelplus.zip

Figured out the problem, I forgot a $ for the LDA # STA CTRL to start DMA. I'm now getting a display, and it looks like what I'm expecting (I think...) Unfortunately, I'm not in a position to recompile MESS for myself (thus my request for a pre-compiled debug binary). Thanks for the heads up on the DMA timing. I thought that might be true. One of the documents gives some timing values, but I'm not sure whether two byte indirect requires 9 or 12 cycles per character (9 makes sense to me, 3x1 for the character & 3x2 for each of the graphic bytes). Well, maybe I'll just make something which looks cool on an emulator, even if it can't work on the actual hardware.

My 2 cents as an outside observer: - first priority is for those people who have the ability (and time and inclination) to work with the source code to speak up and get in contact with one another. - the next priority would be to establish a working compile & test environment (documenting what needs to be done so it can be easily duplicated), and maybe a code library (like sourceforge) - only then should changes be attempted to the code, either as a concentrated or individual efforts As far as WAD files go there are two logical options: either determine what is required to convert a standard Doom 1 WAD file to Jaguar format (and then developing a conversion tool), or modify the Jag code to handle standard WADs. The conversion tool might be easier, especially since a comparison with the basic Doom WAD with the JagWAD should be possible. (I'm also a great believer in not making large code changes if I can get away with it.)

Dan, would it be possible to get the debug version of V7800 (or a Win32 MESS/7800 debug version)? My current test application (working on a demo which uses overlapping tiles) crashes on startup. (I've tried your demo, it does the same thing....) Just some assurance that the BIOS gets the checksum right would be nice. And a question - how accurate/reliable is V7800 or MESS when it comes to DMA timing? I have a feeling that my demo is pushing the limits of what Maria will do in 456 cycles. Or should I budget for both a real 7800 and Chad's Cuttle78?

Check out Dan Boris's 7800 page to start. There are other pages around with some more tidbits of info, but I should warn you that there is far less info & sample code available than for the 2600. I've started fiddling with the 7800 (via emulator) myself, though I haven't gotten beyond the blank screen stage. (No z26.log either, sniff.) My current plan is to disassemble (my own disassembler, but Disasm now handles 7800) a couple of games and try to figure out what I've done wrong.

What Manuel is referring to is an idea I put forth on the Stellalist: would it be possible to connect two 2600s together via the joystick port and create a head-to-head "networked" version of Skeleton. IIRC, we concluded that although it is probably technically possible, there are no plans to do so because: 1. Lack of emulator support would make it difficult to program & debug. 2. I would need 2 TVs, 2 VCSs and 2 Superchargers 3. No market because few people would have the required environment My current plan for head-to-head Skeleton is a top/bottom split screen. And one of these days, I'll find the time & drive to sit down and program it.

Google is your friend: http://www.pospisil.com.au/vintage/wizzard...ith_wizzard.htm Looks like another 6502 console/computer, but this time made in Hong Kong for sale in Australia.

I've thought about this, and I'm fine with signing just the label.

The console controllers also gained intelligence; they have chips in them, rather than just being passive switches and potentiometers. This was for three reasons: 1. number of wires - instead of requiring one wire for each button (or four or more for joysticks/pads), a modified UART (parallel to serial converter) could allow a single wire to handle all of the buttons. 2. analog to digital conversion - the Atari uses a simple resistor/capacitor/time circuit to perform analog to digital conversion for paddles. Unfortunately, this requires significant overhead in the game since it must continually poll the result. The POKEY chip automated this, but it became more efficient and effective to have this done in the controller (also allowing for the digital signal to be sent over the same wire as the buttons) 3. bi-directional functions - the N64 had the rumble and memory packs, the Dreamcast had the VMU

A typical (non-HDTV) NTSC or PAL tube is has a nominal aspect ratio of 4:3 (aka 1.33). However, the picture often goes beyond the edges of the screen (overscan). This sometimes can be adjusted, though not necessarily by the owner. There is also no true specification for how much of the TV signal is picture versus blanking. The DVD (NTSC) spec of 84% (720/858) horizontal and 91% (480/525) vertical is probably close to the maximum. Compare this to the 2600/7800 standard of 70% (160/228) horizontal and 73% vertical (192/262). This all can be extremely frustrating when trying to draw a true circle or square on a standard TV.

Basically, if the player and the Skeleton occupy the same square, the Skeleton hits the player for 1-10 damage (random, but with a bias for 10) instead of moving. Have you been able to finish the game (all 80 Skeletons)? Maybe an additional challenge is to see how much life you have left when you defeat all 80 Skeletons. Or turn off the direction indicator, and use the sound cues alone. I will give some thought to possible difficulty variations (and how to implement them).

The critical items are the total number of lines NTSC:262 PAL:312 (particularly PAL which will go black&white on an odd number of lines) and 3 lines of VSYNC (turning VSYNC off & on right after WSYNC). Emulators are typically more tolerant of the incorrect number of lines than TVs (use Z26's video mode #9), though some TVs may handle a bad number of lines. It's also important to use a consistent number of lines (especially when changing kernels), or the screen will jump. For Skeleton+ I added 11 lines for the counters (NTSC:201 visible, PAL:239 visible) and it displays fine on my ancient 20" Zenith. I just adjusted the timers I use for vertical blanking. Horizontal resolution is fixed. The 2600 has 160 onscreen pixels. The 7800 has 320 pixels (but 160 pixel positioning).

Correct, there are 8 mazes and 10 Skeletons per maze. However, each Skeleton is stronger than the previous one. So at 51 Skeletons, each Skeleton is requiring an average of 7 shots to kill. That will be around 10 shots per Skeleton for the last 10. I would like to make Skeleton+ as good as possible, and difficulty level is a big part of why Skeleton+ exists. But too easy can be as bad as too difficult. Any suggestions? Less life to start? Higher damage? One idea I did come up with was to make the damage time based. So instead of 99 life, you can survive 9.9 seconds of contact.

Sure, I will sign any Skeleton or Skeleton+ cartridges. Just pay for return shipping. I'm not sure about unattached labels though. I need to figure out why or why not. Easier to mail though.

This thread is for those people who feel cheated since they bought Skeleton, and now I've released Skeleton+. Q1. Why now? A1. As I mention on the Skeleton page on my website, the idea of a life counter came to me fairly recently. I realized that it would make Skeleton a much better game. As for why now, I had an opportunity to provide Skeleton via a different outlet and thought it was time to make Skeleton+. Q2. I thought you said you'd never re-release a game. A2. Yes, that is my desire. I have no wish to create bad feelings by re-releasing games (particularly "exclusive" releases which have little differences). But (as per my website), I realized after Skeleton's release that the game wasn't as good as it could be. I recently realized how it could be made significantly better and I was given a reason to make it better. Q3. I thought you said you had run out of space. A3. I had. When I decided to make Skeleton+, I went back through the code looking for places where I could focus my attention on space improvements. What I found were two color lookup tables which were taking up more space than was warranted for their importance. Removal of those tables provided the required space. (This also means that 95% of the rest of the code is unmodified.) Q4. I just bought Skeleton, I want a refund/replacement. A4. Contact either AtariAge or PackRat and they should be able to do something for you. Or find a collector out there and sell it as a limitted edition. (If you have a Hozer cartridge, that's a real limitted edition.) Q5. I hate you, I hate you, I hate you. A5. I'm not Billy Crystal, but have you considered anger management?