old genesis dev environments

evenpace · Post by **evenpace** » Thu Jul 05, 2007 11:28 pm

I have wondered for some time why sega/3rd party developers haven't just open sourced or at the least released binaries of the old dev environments/tools that they used to use to write games! It would also be awesome to get our hands on some source code for games like sonic etc. I guess really it's because they know with a few tweaks/tile changes etc. they can compile the games for game boy advance and sell them as new haha! I wish naughty dog, climax and westone in particular would "give" to the community.. the source for land stalker, wonder boy and rings of power would be incredible! you know that EA must have had some cool tools to streamline development with the amount of games they were putting out too!

evildragon · Post by **evildragon** » Thu Jul 05, 2007 11:41 pm

well, if im not mistaken, those old kits required DOS, and I mean, REAL DOS, not a virtual environment like NT/2000/XP/Vista... It also took a card to be in your computer, a Genesis dev unit which also have a proprietary connector, instead of a cartridge connector, that goes to a cartridge emulator, which is a BIG box...

cdoty · Post by **cdoty** » Fri Jul 06, 2007 1:29 am

It would be interesting to see the GDS mentioned in the programming FAQ. I wonder if any companies ever bought it?

evildragon · Post by **evildragon** » Fri Jul 06, 2007 8:50 am

http://assembler.roarvgm.com/ZAX_Megadr ... e_dev.html

that's the unit im talking about...

8bitwizard · Post by **8bitwizard** » Fri Jul 06, 2007 1:58 pm

Well, I'm more of an Applied Microsystems fan myself (I have two Z80 and a 6809 ICE, looking for an ES1800 with 68000 board and already have a probe), but I didn't realize that the 68000 was that close to the cartridge slot. Either that or the Zax header is offset to the "wrong" side.

I love those Sega-branded floppies.

TmEE co.(TM) · Post by **TmEE co.(TM)** » Fri Jul 06, 2007 2:33 pm

evildragon wrote:http://assembler.roarvgm.com/ZAX_Megadr ... e_dev.html

that's the unit im talking about...

Ancient "flash cart"

These things would be really cool even today. DOS is no problem for me, but finding a 5"1/4 floppy drive is... I had one, but it didn't work.

evildragon · Post by **evildragon** » Fri Jul 06, 2007 3:53 pm

8bitwizard wrote:Well, I'm more of an Applied Microsystems fan myself (I have two Z80 and a 6809 ICE, looking for an ES1800 with 68000 board and already have a probe), but I didn't realize that the 68000 was that close to the cartridge slot. Either that or the Zax header is offset to the "wrong" side.

I love those Sega-branded floppies.

if you're talking about the physical location of the 68000, here's the two possible locations of the 68000 in the model 1's...

Launch Model 1 (heh, my main unit, and CD-Player for my entertainment system)
http://img.photobucket.com/albums/v395/ ... on/sys.jpg

Late Model 1 (my mothers CD-Player)
http://img.photobucket.com/albums/v395/ ... temd12.jpg

For model 2's, it's roughly in the same spot as the early model 1's, the back...

Jorge Nuno · Post by **Jorge Nuno** » Fri Jul 06, 2007 4:16 pm

woow never seen a VA7 model1 genesis... thats a lot of wasted circuit board... that's the "bridge" between model1 & 2

my MD is a V6.8 and has VDP, YM2612, and bus master in distinct components (and an Hitachi 68HC000)

What's usualy the best board revision for overclock?

evildragon · Post by **evildragon** » Fri Jul 06, 2007 5:27 pm

Jorge Nuno wrote:woow never seen a VA7 model1 genesis... thats a lot of wasted circuit board... that's the "bridge" between model1 & 2

my MD is a V6.8 and has VDP, YM2612, and bus master in distinct components (and an Hitachi 68HC000)

What's usualy the best board revision for overclock?

from what i see, the best boards for overclocking are model 1's with DIP CPU's, but lack the rear DB-9 port..

the launch models don't like anything out of sync, and fail to run even just slightly overclocked (the glu-chips can't handle it)...

the VA7 is sorta hard to overclock, but works too..

Jorge Nuno · Post by **Jorge Nuno** » Fri Jul 06, 2007 6:07 pm

Well it seems mine is one of those, it lacks the ext port but it has the solder pads in there, some day i'll test the maximum overclock

(it works well with the 13MHz with sound)

I always thought the earliest revision doesn't clock well because of the signetics 68000

that VA7... that 315-5487 it seems to be very similar to the model2 315-5660, and mine has that FC1004 printing too, but its probably nothing because te pins seem to have the same function... can you tell me if a EN/JP jumper is connected to pin109 of that IC, or connected to ground?

BTW if that chip is really equal to 315-5660 the NTSC/PAL is at pin #46

my pin numbers are starting left from the small depression at the upper left in both chips

that was really off topic

8bitwizard · Post by **8bitwizard** » Fri Jul 06, 2007 7:12 pm

TmEE co.(TM) wrote:Ancient "flash cart" These things would be really cool even today. DOS is no problem for me, but finding a 5"1/4 floppy drive is... I had one, but it didn't work.

Actually it's an In Circuit Emulator. It replaces the 68000 entirely, using its own 68000 with extra support for hardware single-step and breakpoints and trace.

They usually have RAM which appears on the CPU bus so you can not only replace cartridge memory with RAM, but you can even bypass a ROM in the target hardware.

ICE > ROM emulator > Flash cart

evenpace · Post by **evenpace** » Fri Jul 06, 2007 7:31 pm

How many people here have actually written working engines/pieces of engines for the genesis? There should be some sort of community code repository so that people aren't reinventing the wheel every time they want basic scrolling, sprite collision detection, parallaxing etc. Believe me I don't want something for nothing but I do want to know what has/hasn't been done before I start writing stuff myself. (I downloaded steffs dev kit last night and have yet to look throught it but it looks promising!).

Fonzie · Post by **Fonzie** » Fri Jul 06, 2007 7:37 pm

Yo evenpace.
In a practical point of view, you should code yourself scrolling or sprite collide because :
- Its more fun

- You learn more things

Joke apart,
- Optimization is really required on a 8mhz cpu, you may not use "general" functions for it as it would not fit perfectly with your other piece of code.
- Each demo/game already done uses really custom code (I assume) that would not be easy to understand for a beginner.

Just my point of view ^^

Welcome and don't hesitate to open your own thread if you have questions as ,yes, many things were done by members in this board and they would be pleased to answer

TmEE co.(TM) · Post by **TmEE co.(TM)** » Fri Jul 06, 2007 9:32 pm

I'm working on a engine for mean action game, but I WILL NOT USE CODE THAT HAS BEEN WRITTEN BY OTHER PEOPLE, I only try to understand it, and use the new knowledge on my own stuff. I like doing things myself... lots of fun, lots of... debugging, the source of all fun

evildragon · Post by **evildragon** » Fri Jul 06, 2007 9:48 pm

Jorge Nuno wrote:Well it seems mine is one of those, it lacks the ext port but it has the solder pads in there, some day i'll test the maximum overclock

(it works well with the 13MHz with sound)

I always thought the earliest revision doesn't clock well because of the signetics 68000

that VA7... that 315-5487 it seems to be very similar to the model2 315-5660, and mine has that FC1004 printing too, but its probably nothing because te pins seem to have the same function... can you tell me if a EN/JP jumper is connected to pin109 of that IC, or connected to ground?

BTW if that chip is really equal to 315-5660 the NTSC/PAL is at pin #46

my pin numbers are starting left from the small depression at the upper left in both chips

that was really off topic

a lot of people thought it was because of the signetics.. it was later proven false, that the motherboard actually really can't tollerate an overclock.. stinks too, because that motherboard has the best sound (unmodified), and has no TMSS...

im not able to test the VA7, as my mother has it now.. she uses a broken Sega CD with it to play music CDs.. (the Sega CD's CD controller has memory problems, and can't boot a game, but can play a music CD..)

and for your genny with solder pads for the rear port, GREAT modding model.. that was my first model 1.. i installed a military grade CPU in mine, and installed the rear DB-9 port..

http://blackevilweredragon.spymac.com/db9mod.jpg

(ignoring the middle pin, just connect the outer pins, that's it.. oh, and find a female DB-9 connector)..

http://blackevilweredragon.spymac.com/68010-Genesis.jpg

that's the military grade 68000 I installed.. the URL says 68010, because when I installed it, I thought it was a 68010.. I then contacted HP because it's their in-house number, and it turned out to be a regular ceramic 68000..