Pete's QBASIC Site

QB game remakes for Sega MD/Genny ?

2008-08-24T17:10:25-05:00

Hrm...must have been someone else then. Sorry 'bout that. Reason I say it is because the text was quite different than what I originally wrote, and it was uploaded to your directory on the server. No one else had access to your directory. As for the other comment, I was still a bit peeved at the time. I apologize, and will edit the post.

Much appreciated.
Perhaps wherever I copy/pasted the article from had altered the text, but I made it a point not to alter anything. Thanks for editing your post.

Statistics: Posted by w1nt0p — Sun Aug 24, 2008 5:10 pm

QB game remakes for Sega MD/Genny ?

2008-08-24T05:08:32-05:00

Hrm...must have been someone else then. Sorry 'bout that. Reason I say it is because the text was quite different than what I originally wrote, and it was uploaded to your directory on the server. No one else had access to your directory. As for the other comment, I was still a bit peeved at the time. I apologize, and will edit the post.

Statistics: Posted by Nodtveidt — Sun Aug 24, 2008 5:08 am

QB game remakes for Sega MD/Genny ?

2008-08-24T17:09:00-05:00

irrelevant post removed.

Moderators: please remove this empty post. thanks

Statistics: Posted by w1nt0p — Sun Aug 24, 2008 12:52 am

QB game remakes for Sega MD/Genny ?

2008-08-14T14:48:01-05:00

Thanks for enlightening me on the 5 ports part I love MD controller ports... 6-bit bidirectional parallel port (which each bit's direction can be configured independently) or 4800baud(I may be wrong with that number) RS-232C serial port. I like MD HW level, things are made so easy to deal with, and the system is highly moddable too, my MD2 : http://www.hot.ee/tmeeco/MYSMD2.JPG

I don't have any babies around, but I'm still rather busy ... I need to work out palettes for the GFX I exctracted and learn to understand the uncommented code for some things like level related stuff. Also, the game is using standard VGA palette

Statistics: Posted by TmEE — Thu Aug 14, 2008 2:48 pm

QB game remakes for Sega MD/Genny ?

2008-08-14T09:18:03-05:00

From what I understand, the five port setup is for timing reasons. Each controller status is read in sequence, and the software interprets the controllers in said sequential order. This was correlated by certain older software exhibiting strange behavior when the multitap was used (such as two controllers working for single player games but only certain switches on one and certain others on the second actually having any effect). Back then, software designers (even Hudson's own staff) were not 100% familiar with how the controller port was timed, so errors like that appeared with the multitap. But they got the hang of it eventually, and by the time the PCE made it to US shores, only one game (China Warrior) suffered from the problem (since the only change to this 1987 game was the title screen). Having only 4 ports would also have been a marketing disadvantage, since the NES had a four-player option and NEC wanted to beat Nintendo in any way possible (Hudson didn't care either way; after all, they were Nintendo's first third-party).

In any event, have you made any progress with the conversion? I've had no free time so nothing's happened over here, heh. Having a new baby in the house tends to suck up any notion of "free time".

Statistics: Posted by Nodtveidt — Thu Aug 14, 2008 9:18 am

QB game remakes for Sega MD/Genny ?

2008-08-13T07:47:02-05:00

my bad about PCE not being able to flip sprites... I knew it couldn't flip tiles...
Looking at 1 controller port on HW wise makes no real sense though... its not like its difficult to add another port... only reason would be to cut cost. On another note, the multi tap having 5 controller ports is a little odd... things are still binary, thus 4 or 8 would have made more sense... but then again, MD has 3 controller ports in HW (on later models its omitted)...

Statistics: Posted by TmEE — Wed Aug 13, 2008 7:47 am

QB game remakes for Sega MD/Genny ?

2008-08-24T05:09:09-05:00

Yeah some of the doc is inaccurate like I said before, plus some of it was modified by someone. Dunno what you mean in terms of flipping though...the PCE can't do tile flipping but it most certainly can do sprite flipping. It'd be an awfully useless game machine if it couldn't flip sprites. At the time, I didn't know about shadow/highlight mode, only about the false HAM mode rumor. As for the memory aspect...I didn't fully understand how scratch RAM was utilized at the time (C compilers tend to hide these details) so that's the one area where I was quite wrong. For the port issue, I don't understand why it would be nonsensical...that's really the reason it was created like that, according to one of Hudson's engineers on the development team of the machine (I don't remember his name...Japanese names are often hard to remember).

Yeah, it was probably a bit biased and some things were neglected, but it was written a long time ago and my knowledge of the machines has expanded since then. But despite that, I still very much prefer the PCE hardware over the MD hardware, though in reality the two machines complement each other nicely...what's lacking in one is made up for in the other, and vice versa.

Statistics: Posted by Nodtveidt — Mon Aug 11, 2008 10:13 pm

QB game remakes for Sega MD/Genny ?

2008-08-11T09:44:36-05:00

I'm aware that the 6280 is faster than 68000... each CPU has edge on some areas... I like 68000 more that any other CPU as its very orthogonal, has lot of registers and all are 32bit (one isn't, but its not general purpose anyway) and flat address space.

You've got an innaccuracy in Video... all 64 colors can be used for both sprites and backgrounds, not 32 for BG and 32 for Sprites. There's only 8x8 tile sytem in standard res, and 16x8 in interlace mode2 (320x480). There is no CPU time required to maintain res (that's how I understood)... everything is managed by the VDP. Resolutions are 256/320 x 224/240/448/480 (240/480 can only be used in 50Hz mode). MD VDP has line scrolling table, and you don't need Hints to do the "fake" extra background layers (you can, but why bother...). Only area where PCE wins is overall res, and palette count. You forgot to mention PCE can't to tile/sprite flipping. You've also forgot that MD can do Shadow/Highlight, thus tripling stock 512 colors (though the use of S/HL sets some limitations of some stuff).

Sound : There's 3 PSC tone channels + 1 noise channel. You can use both 68K and Z80 to control the sound chips, there's total of 10 sound channels. Since you have Z80, which runs totally independently from 68K, and which can access the rest of the system, you really don't need to use 68K unless you don't need every ounce of performance.

Memory : code swapping ? you run code directly from ROM unless you do some really quirky stuff with hardware (such as manually initializing MCD or writing flash ROM). when CD is added, 256K of its RAM is mapped into MD address space and part of main RAM is turned into control registers...

The lack of an additional port on the PCE/TG16 was thought to be a "money scheme" to market more peripherals, but in reality it was done for programming simplicity, giving a distinct edge to multiplayer game programmers on the PCE.

? non-sensial a bit.... ?

No offence, but what you've written is a bit biased and some things are neglected...

Statistics: Posted by TmEE — Mon Aug 11, 2008 9:44 am

QB game remakes for Sega MD/Genny ?

2008-08-10T19:46:26-05:00

Actually, the PCE has a 6280 which is a 6502 variant. In terms of instructions, it's pretty on-par with the Genesis' 68000, even surpassing it in some ways. And yeah, the Genesis video chip could have used some serious improvements. Having such limited colors is such a damn drag. 32 palettes are available on the PCE...16 for backgrounds and 16 for sprites...from the same exact color pool as the Genesis (3/3/3 RGB triad).

I actually wrote out a $$$ for some people awhile back. There might be some slight inaccuracies in it, as I've learned more about the consoles since then, but check it out:

http://www.nodtveidt.net/developerx/segavspce.html

Statistics: Posted by Nodtveidt — Sun Aug 10, 2008 7:46 pm

QB game remakes for Sega MD/Genny ?

2008-08-10T06:36:45-05:00

PPUs are in NES and SNES, I have a VDP in MD

Other than palettes, its better at some aspects than what you have in PCE/TG16... 2x Scrolls, line scrolling, vertical tile scrolling, tile/sprite flipping...
More palettes would have been nicer though (4 for BG, 4 for Sprites as in some arcade machines that use exact same VDP MD uses... stupid Sega).
I'm not too familiar with PCE/TG16... the facts that I don't have one and that it has 6502 in it doesn't make me want to look at it really...

Statistics: Posted by TmEE — Sun Aug 10, 2008 6:36 am

QB game remakes for Sega MD/Genny ?

2008-08-09T21:29:50-05:00

Yes, the wonderful limitations of its absolute crap PPU.

Statistics: Posted by Nodtveidt — Sat Aug 09, 2008 9:29 pm

QB game remakes for Sega MD/Genny ?

2008-08-04T05:19:08-05:00

hehe

I have extracted all the graphics, and I'm glad the total color count is 60... it will still be a little headache getting things fit into 4x 15 color palettes + 1 color...

Also, mr. Angelo has drawn all 8 enemies and his uncommented code is not the greatest :/

Statistics: Posted by TmEE — Mon Aug 04, 2008 5:19 am

QB game remakes for Sega MD/Genny ?

2008-08-03T21:19:53-05:00

Poor little Z80.

Statistics: Posted by Nodtveidt — Sun Aug 03, 2008 9:19 pm

QB game remakes for Sega MD/Genny ?

2008-07-29T04:39:25-05:00

With my sound engine, I can have 5xFM + 2xPCM + 3(4)xPSG channels of sound... and its 0% of main CPU use, you forgot Z80 in MD (though of real hardware, there is 5% performance hit on 68K as the poor Z80 is moving near 100KB of data a second ).

Statistics: Posted by TmEE — Tue Jul 29, 2008 4:39 am

QB game remakes for Sega MD/Genny ?

2008-07-27T16:10:32-05:00

That would be a good idea. Since you already have sound covered, using MIDIs from WS2 shouldn't be an issue for you. Or really, MIDIs from any source provided they don't use too many instruments. On my hardware of choice, I can "cheat" a bit by simply putting the game on CDROM and using redbook audio and ADPCM samples, freeing up CPU time considerably.

Statistics: Posted by Nodtveidt — Sun Jul 27, 2008 4:10 pm