When the megadrive 1 was released in japan the expansion connector where you put the megacd on was already built in. So, was it from the beginning planned to expand the hardware someday or did sega made an expansion port just in case of ?
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When the megadrive 1 was released in japan the expansion connector where you put the megacd on was already built in. So, was it from the beginning planned to expand the hardware someday or did sega made an expansion port just in case of ?
Good question....
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Nope, extention such like segacd wasn't planned.
What was planned was things like external FDD / CDROM drive. But never a "side system".
The whole design is very bottlenecked because the extension port is very small (256KB x 2) and only one direction (md>extention).
With only a few more signals going through extention port they could have made a setup a LOT more effective... But they didn't, means no planning for such things.
Same issues occurs for 32x, was never planned.
yeah its sort of like how sega put an extra 44 blocks of memory in the dreamcast vmu's that were never used, it (like the sega genesis expantion port) was just for a little "headway" down the road.
Fonzie, that's something that always baffles me. Why make the expansion port if you're not gonna optimize it for going the extra mile, in case you choose to make an add-on system for said expansion port.
Obviously making the cartridge port optimized for use with an add-on system would have been ridiculous, so that's beside the point. We all know the 32X should never have existed.
you could argue the mega cd should have never been since the games look pretty much the same and the 32x should have gone on the side making it a better looking system + 1 less wire and maybe it would have been more succesful that way. ok im just talking silly but you could argue it either way and the mega cd wasnt all that golden most of the time lots of lazy ports of games you can already get on the megadrive.
How limited is the expansion port?
If the Sega CD increased the color palette. Would you need an external cable like the 32x does? Or would the expansion port have been able to do it without an external video cable?
Yes, you'd still need the cable as the video doesn't go to the expansion port. They really should have... along with ALL the CPU signals. They really screwed the pooch when they designed the side expansion slot. Must have been an ex-Microsoft employee that did that part. You know how they are about computers NEVER exceeding certain bounds in the future. ;) :DQuote:
Originally Posted by Eric83
The Expansion port seems like a barely usable floppy/CD connection... (FDWR and DISK signals come to mind)
They should really used the pixel output from the VDP... Man that way the MD could have 15/16/24 bits of color selection along with 8 palettes and possibly more with palette banking (awesome $hit right there) . Damn... But no they sucked big time using the crippled VDP CRAM/DAC, and worse: a 9 bit f_cking serial shift register to select the bank to the Z80 (wtf were they drinking!?)...
Sega failed a lot in the hardware department of the MD.
Yeah, the MD is nice, but it's really just a Master System with a 68000 tacked on and a minor enhancement to the VDP. There's a BUNCH of things they could have done that would have made it far better - like not using a serial port for the Z80 bank. That was REALLY stupid and is a major limit on how useful the Z80 is. Giving two banks instead of one would have also been far better. The 68000 and ram is okay, but they should have made it where the 68000 could access VRAM at any time. That would have made that far better.Quote:
Originally Posted by Jorge Nuno
The reason the Exp. Port feels like a floppy drive connector? It was meant to be one, as some early sketches show, along with a keyboard and an tape deck or something else weird and VERY late 80s.Quote:
Originally Posted by Jorge Nuno
I never saw those sketches, I made my assumption from the signals' names presented on the port.
That's sad... I always laugh at any attempts to make a game console into a computer. One example that comes to mind is the ColecoVision and ADAM computer...Quote:
Originally Posted by Enigmus
The 32x was a lot better off though, the cartridge connector is far more capable than the expansion connector. (address space, signals avaialble, etc)Quote:
Originally Posted by Fonzie
Yeah, with no YS, you couldn't support video overlay if you wanted to. Too bad the expansion connector wasnt just an auxiliary cartridge connector. (isn't that what the SMS did for it's EXP port? -I think a drawback on the SMS was that the exp port couldn't support a plug-in YM2413 like the Mk.III, that would heve been great -particularly since nothing even used that expansion)Quote:
Originally Posted by Chilly Willy
Even so they probably could have just omitted the expansion connector alltogether and used the cartridge connector for the CD instead (with a layout more like the Jaguar's top loading CD with passthrough cartridge slot), maybe even cheaper with that configuration (top loading drive), but FCC approval might have been more of an issue.
Or they could have omitted the exp port entirely and added the pixel bus to the cartridge port as well, then using only the cart slot for peripherals. (and maybe even allow some cartridges to take advantage of that with onboard hardware)Quote:
Originally Posted by Jorge Nuno
Having the RGB signals as well would have meant no need for external video mixing as well.
They could have set it up with outboard pins on the cart slot, like SNES, to avoid rasing costs of standard cartridges. (and trade some cost with the expansion connector removed, or maybe just putting the necessary signals and increased addressing on the expansion connector would be preferred -though that removes the enhanced cartridge possibility)
With YS and the pixel bus I think you could do the dual VDP idea Chilly Willy proposed. (2 genesis VDPs, supporting overlay, both in a Supergrafx manner and capable of combining pixels to have 8-bit palettes -256 colors with an external RAMDAC supporting a larger palette as well) And with RGB on the connector as well, no mixing cable either!
I think a 72-pin connector would probably have been enough for all that.
Nothing wrong with that IMO, Adam was horribly executed though, could have been more like MSX. (simple console with external expansion capabilities plus CV compatibility) Or more precicely, like Sega SC-3000, except with the CV being more popular than the SG-1000 at the respective times.Quote:
Originally Posted by Guntz
Same for the other way around, C64GS, Commodore MAX, A5200, XEGS, CD32, etc are all tied to poor execution or other external factors (like a crumbling company with the CD32, combined with barred US release), something like the XEGS might have worked OK in place of the 5200 (still no lockout though due to A8 compatibility), and a C64 based gaming system might have been OK if it facilitated simple ports (ie full 64 kB and minimal keypad with most commonly needed keys), just a cheaper, cart-cased system with very limited expandability, the MAX was way too limited (RAM) and the 64GS was both way too late (needed to be there by '85 or '86) and had compatibility problems due to missing keys. (the latter could have been fixed in software and facilitated by controllers with a couple more buttons)
However, this isn't even the general case with the Genesis Disk drive. It may have been inteded for some additional non-gaming applications, but I think it was primarily intended to be what the Famicom Disk system was, support for an alternate media. (namely much cheaper and more flexible than ROM cartridges -and writable) The obvious problem is ease of piracy (especially due to ease of production), which the FDC experienced in spite of semi-propritary format. (and of course came as a major problem with optical discs as well)
http://sega-16.com/forum/showthread....d=1#post209573
Hey, I got to thinking in th eabove theread and realized that Sega could have gone the route NEC went and Nintendo was planning to with a more or less bare bones CD drive with separate system card/cart/module plugging into the cart slot. But going further this would have also allowed for the module w/out the CD unit if a cart slot was added, so sort of like an earlier 32x, and with the greater flexibility of the cartridge slot, possibly more like the 32x. (ie added VDP) And allow the 2 units to be sold separately, thus allowing expansion module users to upgrade to CD as well.
Of course, that would still exclude any neat stuff possible with the pixel bus and still require an external mixing cable for video expansion.
Also, a revision to my previous post: I don't think RGB would even be necessary if using the pixel bus for enhanced video with dual VDPs and such, just a separate A/V port on the expansion unit. (so long as normal genesis games still displayed fine via that AV connection, I'm not entirely sure if that would work)