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Some SG-1000 questions that have been bugging me:

1) Is it possible to play SG-1000 ROMs on a US SMS via flashcart?
a) If so, do they need to be patched in some way in order to get around the BIOS/region check?
b) If not, can the console itself be modded to make it work?

2) Does any version of the Mark III/SMS hardware display SG-1000 games with the correct palette (i.e. without making the colors too dark)?

3) Is there a comprehensive list of SMS games that run in SG-1000 mode, like Super Boy 2 and Dr. Hello?
a) Are those games (theoretically) playable on original SG-1000 hardware?
(EDIT: OK, based on the post at the bottom of this page, it looks like Super Boy 2 may need additional RAM that the SG-1000 doesn't have. Is this true of other SG-1000 mode SMS games as well?)

4) Is there a comprehensive list of undumped SG-1000 games? I'm especially curious about games for which SG-1000 versions are believed to exist, but which have only emerged on MSX et al.

5) Is there a 100% comprehensive list of all SC-3000 software?
a) Has any of it been rewritten to work on bare SG-1000 hardware? (i.e. disk- or tape-based software that, once it loads, doesn't depend on anything but the core SG-1000 routines)

Thanks very much for any and all replies, and forgive me if I've overlooked anything.

goldenband wrote

1) Is it possible to play SG-1000 ROMs on a US SMS via flashcart?

Yes.

goldenband wrote

a) If so, do they need to be patched in some way in order to get around the BIOS/region check?

Yes. You need to add a valid header at $7ff0, and possibly relocate any code/data in that part.

goldenband wrote

b) If not, can the console itself be modded to make it work?

You can also disable or replace the console BIOS to avoid the header checks, or use a flashcart with a menu (since the console will only check the menu's header).

goldenband wrote

2) Does any version of the Mark III/SMS hardware display SG-1000 games with the correct palette (i.e. without making the colors too dark)?

No.

goldenband wrote

3) Is there a comprehensive list of SMS games that run in SG-1000 mode, like Super Boy 2 and Dr. Hello?

No, but people are welcome to add this data to our site :)

goldenband wrote

a) Are those games (theoretically) playable on original SG-1000 hardware?
(EDIT: OK, based on the post at the bottom of this page, it looks like Super Boy 2 may need additional RAM that the SG-1000 doesn't have. Is this true of other SG-1000 mode SMS games as well?)

Pretty much, yes, just the RAM requirement is an issue.

goldenband wrote

4) Is there a comprehensive list of undumped SG-1000 games? I'm especially curious about games for which SG-1000 versions are believed to exist, but which have only emerged on MSX et al.

I think the reverse is more common - MSX conversions only really happened in Korea, and many of our Korean dumps have been of games for which the MSX version is undumped. Also, I think MSX conversions will use more than 2KB of RAM so they're properly SMS versions of MSX games.

goldenband wrote

5) Is there a 100% comprehensive list of all SC-3000 software?

No. There's a huge amount of tiny tape releases in AU/NZ to catalogue. The biggest list is probably this:

http://homepages.ihug.co.nz/~atari/sc3000.html

goldenband wrote

a) Has any of it been rewritten to work on bare SG-1000 hardware? (i.e. disk- or tape-based software that, once it loads, doesn't depend on anything but the core SG-1000 routines)

I think most tape software works like this, but nobody's done any conversions that I know of. Disk software may well need 64KB of RAM. There are a few ROM to disk (piracy) conversions.

Thanks very much for your replies!

Maxim wrote

Yes. You need to add a valid header at $7ff0, and possibly relocate any code/data in that part.

Interesting, OK -- so it can be a somewhat involved process. If the SMS needs a header at $7ff0, how do Japanese systems use that part of the address space? Is that address implicated in any cross-region crashing issues?

Maxim wrote

goldenband wrote

2) Does any version of the Mark III/SMS hardware display SG-1000 games with the correct palette (i.e. without making the colors too dark)?

No.

Eep. OK, that's good to know -- so if you want a correct palette, right now it's either use a SG-1000/SC-3000, or play one of the CV/MSX ports. :)

Is there an easy/consistent ROM hack that can fix the issue when using flashcarts? I assume the Mark III/SMS has the matching colors in its palette, yes? I've read that this Game Gear cart can be set up to accommodate the SG-1000 palette, but of course the Game Gear has a much larger colorspace.

Maxim wrote

goldenband wrote

3) Is there a comprehensive list of SMS games that run in SG-1000 mode, like Super Boy 2 and Dr. Hello?

No, but people are welcome to add this data to our site :)

:)

Maxim wrote

goldenband wrote

a) Are those games (theoretically) playable on original SG-1000 hardware?

Pretty much, yes, just the RAM requirement is an issue.

Good to know. I wonder how many use more than 8K of additional memory -- and thus, whether it'd be possible to turn The Castle into a multicart for any of those games. Of course, it'd be a shame to destroy that cart, and one could just use a SC-3000. (Not that it's exactly easy to get one's hands on that machine where I live.)

Thanks for that link to SC-3000 software, BTW. One of the reasons I'm drawn to the SG-1000 is that the notion of playing through a system's entire library is rather seductive -- it's like knowing all of Beethoven's piano concertos by heart. I'd love to check out some of those SC-3000 text adventures and such; right now I don't think there's a viable SC-3000 emulator for PPC Mac, though.

goldenband wrote

Eep. OK, that's good to know -- so if you want a correct palette, right now it's either use a SG-1000/SC-3000, or play one of the CV/MSX ports. :)

The CV/MSX ports on SMS suffer from the same palette problems. Also MSX ports AFAIK have different sound from the original as the chips arent exactly the same.

Quote

Is there an easy/consistent ROM hack that can fix the issue when using flashcarts? I assume the Mark III/SMS has the matching colors in its palette, yes? I've read that this Game Gear cart can be set up to accommodate the SG-1000 palette, but of course the Game Gear has a much larger colorspace.

It was found that GG use the standard palette entries to render SG-1000-ish video modes so yes it can be done on GG. MarkIII/SMS can't afaik.

goldenband wrote

If the SMS needs a header at $7ff0, how do Japanese systems use that part of the address space? Is that address implicated in any cross-region crashing issues?

They don't treat it specially at all. Cross-region issues are solely due to timing differences between NTSC and PAL; there should be no crashes with US-released games on a Japanese system and vice versa (just the cart shape problem).

goldenband wrote

Is there an easy/consistent ROM hack that can fix the issue when using flashcarts? I assume the Mark III/SMS has the matching colors in its palette, yes?

The SMS palette is not changeable, it's apparently "hard-coded" into the chip. Palette changes do not affect the display.

goldenband wrote

I'd love to check out some of those SC-3000 text adventures and such

Well, there's not really any emulators with tape support yet (we need to choose a tape format, at least) so the tape dumps aren't really available either.

goldenband wrote

Maxim wrote

goldenband wrote

3) Is there a comprehensive list of SMS games that run in SG-1000 mode, like Super Boy 2 and Dr. Hello?

No, but people are welcome to add this data to our site :)

:)

I have started work on this:

http://www.smspower.org/Tags/LegacyVideo

If you want to help us build the list, let us know... it is very easy.

Bock wrote

The CV/MSX ports on SMS suffer from the same palette problems. Also MSX ports AFAIK have different sound from the original as the chips arent exactly the same.

Sorry, I meant going from the SG-1000 to the CV, since a bunch of ColecoVision enthusiasts have been porting tons of SG-1000 games: Gulkave, Pitfall II, Girl's Garden, Black Onyx (with translation)...a good chunk of the library has been done. Those ports can be pretty much perfect, whereas the MSX has one less sound channel IIRC.

Maxim wrote

goldenband wrote

If the SMS needs a header at $7ff0, how do Japanese systems use that part of the address space? Is that address implicated in any cross-region crashing issues?

They don't treat it specially at all. Cross-region issues are solely due to timing differences between NTSC and PAL; there should be no crashes with US-released games on a Japanese system and vice versa (just the cart shape problem).

I guess I'm confused (and likely somewhat naive) because I'd assume that if the console is looking for a header at a particular address, then it's reserved excluslvely for that use and any other content at that location would cause problems. I take it there's some bit pattern that tells the console "OK, this is a header, treat this as such". Does the Japanese console look for a similar header at a different location?

Maxim wrote

goldenband wrote

Is there an easy/consistent ROM hack that can fix the issue when using flashcarts? I assume the Mark III/SMS has the matching colors in its palette, yes?

The SMS palette is not changeable, it's apparently "hard-coded" into the chip. Palette changes do not affect the display.

So whenever the console runs in SG-1000 video mode, the available colors are absolutely fixed in hardware, and there's no way to access the SMS's broader colorspace -- it's those 16 overly dark colors, and nothing but. Is that correct?

I struggled with this because I was (incorrectly) assuming that the issue was mapping a 4-bit palette into a 6-bit colorspace, i.e. so that the wrong values were being requested from the SMS's video hardware.

Is there any documentation on how/why the color mismatch happened, and how consumers reacted to it at the time? Was it a design error by Texas Instruments, or something deliberately done to save money/minimize complexity?

Maxim wrote

I have started work on this:

http://www.smspower.org/Tags/LegacyVideo

If you want to help us build the list, let us know... it is very easy.

Hey, fantastic! I'd be happy to help, though right now the only other one I know about is Dr. Hello. But that doesn't seem to have a game page just yet.

BTW thanks to all responsible for dumping Dr. Hello, I had a blast playing it over the past couple days -- finally beat Level 20 on Hard! -- and actually, I think I prefer it to the original.

goldenband wrote

I guess I'm confused (and likely somewhat naive) because I'd assume that if the console is looking for a header at a particular address, then it's reserved excluslvely for that use and any other content at that location would cause problems. I take it there's some bit pattern that tells the console "OK, this is a header, treat this as such". Does the Japanese console look for a similar header at a different location?

It doesn't check for this header. Check out this page for detailed look into the different boot roms:
http://www.smspower.org/Development/BIOSes

As for the palette on SMS, it is believed that is no way to change those colors, but who knows if some hard/soft hacks would permit it. ?

Short version: US and European SMSes look for a header. Japanese ones don't. GGs check for a header if they have the blue splash screen on startup.

The "legacy video mode" colours seem fixed. The system totally ignores the palette in this mode. Unless there's some "back door" way to fix it, it's just impossible. Sega even went so far as to re-release some SG-1000 games with palettes adjusted to look better on the Mark III (with the bad palette); if there was some way around it I'm sure they'd have used it.

My suspicion is that someone in Sega looked up the TMS9918a colour list, which looks like:

Quote

(Transparent)
Black
Medium Green
Light Green
Dark Blue
Light Blue
Dark Red
Cyan
Medium Red
Light Red
Dark Yellow
Light Yellow
Dark Green
Magenta
Gray
White

...and then assigned fixed 6-bit (SMS) colours based on these descriptions (e.g. #FF0000 for Light Red), without regard to what they actually looked like on-screen. I've put a comparison here:

http://www.smspower.org/Development/Palette#MasterSystemMarkIII

Maxim wrote

I have started work on this:

http://www.smspower.org/Tags/LegacyVideo

SG-1000 Yie Ar Kung-Fu has been given this tag. Is this a mistake?

Paul Baker wrote

Maxim wrote

I have started work on this:

http://www.smspower.org/Tags/LegacyVideo

SG-1000 Yie Ar Kung-Fu has been given this tag. Is this a mistake?

No mistake ever happened ;)
(I edited the page)

I saw "MSX Port" and didn't apply my brain to the system field... despite what I wrote on http://www.smspower.org/Tags/LegacyVideo .

Author	Message
goldenband Joined: 24 May 2010 Posts: 115 Location: New York	Some SG-1000 questions Posted: Sun Aug 08, 2010 11:18 pm
	Some SG-1000 questions that have been bugging me: 1) Is it possible to play SG-1000 ROMs on a US SMS via flashcart? a) If so, do they need to be patched in some way in order to get around the BIOS/region check? b) If not, can the console itself be modded to make it work? 2) Does any version of the Mark III/SMS hardware display SG-1000 games with the correct palette (i.e. without making the colors too dark)? 3) Is there a comprehensive list of SMS games that run in SG-1000 mode, like Super Boy 2 and Dr. Hello? a) Are those games (theoretically) playable on original SG-1000 hardware? (EDIT: OK, based on the post at the bottom of this page, it looks like Super Boy 2 may need additional RAM that the SG-1000 doesn't have. Is this true of other SG-1000 mode SMS games as well?) 4) Is there a comprehensive list of undumped SG-1000 games? I'm especially curious about games for which SG-1000 versions are believed to exist, but which have only emerged on MSX et al. 5) Is there a 100% comprehensive list of all SC-3000 software? a) Has any of it been rewritten to work on bare SG-1000 hardware? (i.e. disk- or tape-based software that, once it loads, doesn't depend on anything but the core SG-1000 routines) Thanks very much for any and all replies, and forgive me if I've overlooked anything.

Maxim Site Admin Joined: 19 Oct 1999 Posts: 11272 Location: London	Posted: Mon Aug 09, 2010 9:21 am
	goldenband wrote 1) Is it possible to play SG-1000 ROMs on a US SMS via flashcart? Yes. goldenband wrote a) If so, do they need to be patched in some way in order to get around the BIOS/region check? Yes. You need to add a valid header at $7ff0, and possibly relocate any code/data in that part. goldenband wrote b) If not, can the console itself be modded to make it work? You can also disable or replace the console BIOS to avoid the header checks, or use a flashcart with a menu (since the console will only check the menu's header). goldenband wrote 2) Does any version of the Mark III/SMS hardware display SG-1000 games with the correct palette (i.e. without making the colors too dark)? No. goldenband wrote 3) Is there a comprehensive list of SMS games that run in SG-1000 mode, like Super Boy 2 and Dr. Hello? No, but people are welcome to add this data to our site :) goldenband wrote a) Are those games (theoretically) playable on original SG-1000 hardware? (EDIT: OK, based on the post at the bottom of this page, it looks like Super Boy 2 may need additional RAM that the SG-1000 doesn't have. Is this true of other SG-1000 mode SMS games as well?) Pretty much, yes, just the RAM requirement is an issue. goldenband wrote 4) Is there a comprehensive list of undumped SG-1000 games? I'm especially curious about games for which SG-1000 versions are believed to exist, but which have only emerged on MSX et al. I think the reverse is more common - MSX conversions only really happened in Korea, and many of our Korean dumps have been of games for which the MSX version is undumped. Also, I think MSX conversions will use more than 2KB of RAM so they're properly SMS versions of MSX games. goldenband wrote 5) Is there a 100% comprehensive list of all SC-3000 software? No. There's a huge amount of tiny tape releases in AU/NZ to catalogue. The biggest list is probably this: http://homepages.ihug.co.nz/~atari/sc3000.html goldenband wrote a) Has any of it been rewritten to work on bare SG-1000 hardware? (i.e. disk- or tape-based software that, once it loads, doesn't depend on anything but the core SG-1000 routines) I think most tape software works like this, but nobody's done any conversions that I know of. Disk software may well need 64KB of RAM. There are a few ROM to disk (piracy) conversions.

goldenband Joined: 24 May 2010 Posts: 115 Location: New York	Posted: Mon Aug 09, 2010 7:54 pm
	Thanks very much for your replies! Maxim wrote Yes. You need to add a valid header at $7ff0, and possibly relocate any code/data in that part. Interesting, OK -- so it can be a somewhat involved process. If the SMS needs a header at $7ff0, how do Japanese systems use that part of the address space? Is that address implicated in any cross-region crashing issues? Maxim wrote goldenband wrote 2) Does any version of the Mark III/SMS hardware display SG-1000 games with the correct palette (i.e. without making the colors too dark)? No. Eep. OK, that's good to know -- so if you want a correct palette, right now it's either use a SG-1000/SC-3000, or play one of the CV/MSX ports. :) Is there an easy/consistent ROM hack that can fix the issue when using flashcarts? I assume the Mark III/SMS has the matching colors in its palette, yes? I've read that this Game Gear cart can be set up to accommodate the SG-1000 palette, but of course the Game Gear has a much larger colorspace. Maxim wrote goldenband wrote 3) Is there a comprehensive list of SMS games that run in SG-1000 mode, like Super Boy 2 and Dr. Hello? No, but people are welcome to add this data to our site :) :) Maxim wrote goldenband wrote a) Are those games (theoretically) playable on original SG-1000 hardware? Pretty much, yes, just the RAM requirement is an issue. Good to know. I wonder how many use more than 8K of additional memory -- and thus, whether it'd be possible to turn The Castle into a multicart for any of those games. Of course, it'd be a shame to destroy that cart, and one could just use a SC-3000. (Not that it's exactly easy to get one's hands on that machine where I live.) Thanks for that link to SC-3000 software, BTW. One of the reasons I'm drawn to the SG-1000 is that the notion of playing through a system's entire library is rather seductive -- it's like knowing all of Beethoven's piano concertos by heart. I'd love to check out some of those SC-3000 text adventures and such; right now I don't think there's a viable SC-3000 emulator for PPC Mac, though.

Bock Site Admin Joined: 08 Jul 2001 Posts: 7445 Location: Paris, France	Posted: Tue Aug 10, 2010 3:59 am
	goldenband wrote Eep. OK, that's good to know -- so if you want a correct palette, right now it's either use a SG-1000/SC-3000, or play one of the CV/MSX ports. :) The CV/MSX ports on SMS suffer from the same palette problems. Also MSX ports AFAIK have different sound from the original as the chips arent exactly the same. Quote Is there an easy/consistent ROM hack that can fix the issue when using flashcarts? I assume the Mark III/SMS has the matching colors in its palette, yes? I've read that this Game Gear cart can be set up to accommodate the SG-1000 palette, but of course the Game Gear has a much larger colorspace. It was found that GG use the standard palette entries to render SG-1000-ish video modes so yes it can be done on GG. MarkIII/SMS can't afaik.

Maxim Site Admin Joined: 19 Oct 1999 Posts: 11272 Location: London	Posted: Tue Aug 10, 2010 9:21 am
	goldenband wrote If the SMS needs a header at $7ff0, how do Japanese systems use that part of the address space? Is that address implicated in any cross-region crashing issues? They don't treat it specially at all. Cross-region issues are solely due to timing differences between NTSC and PAL; there should be no crashes with US-released games on a Japanese system and vice versa (just the cart shape problem). goldenband wrote Is there an easy/consistent ROM hack that can fix the issue when using flashcarts? I assume the Mark III/SMS has the matching colors in its palette, yes? The SMS palette is not changeable, it's apparently "hard-coded" into the chip. Palette changes do not affect the display. goldenband wrote I'd love to check out some of those SC-3000 text adventures and such Well, there's not really any emulators with tape support yet (we need to choose a tape format, at least) so the tape dumps aren't really available either.

Maxim Site Admin Joined: 19 Oct 1999 Posts: 11272 Location: London	Posted: Tue Aug 10, 2010 2:59 pm
	goldenband wrote Maxim wrote goldenband wrote 3) Is there a comprehensive list of SMS games that run in SG-1000 mode, like Super Boy 2 and Dr. Hello? No, but people are welcome to add this data to our site :) :) I have started work on this: http://www.smspower.org/Tags/LegacyVideo If you want to help us build the list, let us know... it is very easy.

goldenband Joined: 24 May 2010 Posts: 115 Location: New York	Posted: Tue Aug 10, 2010 4:56 pm
	Bock wrote The CV/MSX ports on SMS suffer from the same palette problems. Also MSX ports AFAIK have different sound from the original as the chips arent exactly the same. Sorry, I meant going from the SG-1000 to the CV, since a bunch of ColecoVision enthusiasts have been porting tons of SG-1000 games: Gulkave, Pitfall II, Girl's Garden, Black Onyx (with translation)...a good chunk of the library has been done. Those ports can be pretty much perfect, whereas the MSX has one less sound channel IIRC. Maxim wrote goldenband wrote If the SMS needs a header at $7ff0, how do Japanese systems use that part of the address space? Is that address implicated in any cross-region crashing issues? They don't treat it specially at all. Cross-region issues are solely due to timing differences between NTSC and PAL; there should be no crashes with US-released games on a Japanese system and vice versa (just the cart shape problem). I guess I'm confused (and likely somewhat naive) because I'd assume that if the console is looking for a header at a particular address, then it's reserved excluslvely for that use and any other content at that location would cause problems. I take it there's some bit pattern that tells the console "OK, this is a header, treat this as such". Does the Japanese console look for a similar header at a different location? Maxim wrote goldenband wrote Is there an easy/consistent ROM hack that can fix the issue when using flashcarts? I assume the Mark III/SMS has the matching colors in its palette, yes? The SMS palette is not changeable, it's apparently "hard-coded" into the chip. Palette changes do not affect the display. So whenever the console runs in SG-1000 video mode, the available colors are absolutely fixed in hardware, and there's no way to access the SMS's broader colorspace -- it's those 16 overly dark colors, and nothing but. Is that correct? I struggled with this because I was (incorrectly) assuming that the issue was mapping a 4-bit palette into a 6-bit colorspace, i.e. so that the wrong values were being requested from the SMS's video hardware. Is there any documentation on how/why the color mismatch happened, and how consumers reacted to it at the time? Was it a design error by Texas Instruments, or something deliberately done to save money/minimize complexity? Maxim wrote I have started work on this: http://www.smspower.org/Tags/LegacyVideo If you want to help us build the list, let us know... it is very easy. Hey, fantastic! I'd be happy to help, though right now the only other one I know about is Dr. Hello. But that doesn't seem to have a game page just yet. BTW thanks to all responsible for dumping Dr. Hello, I had a blast playing it over the past couple days -- finally beat Level 20 on Hard! -- and actually, I think I prefer it to the original.

Bock Site Admin Joined: 08 Jul 2001 Posts: 7445 Location: Paris, France	Posted: Wed Aug 11, 2010 3:33 am
	goldenband wrote I guess I'm confused (and likely somewhat naive) because I'd assume that if the console is looking for a header at a particular address, then it's reserved excluslvely for that use and any other content at that location would cause problems. I take it there's some bit pattern that tells the console "OK, this is a header, treat this as such". Does the Japanese console look for a similar header at a different location? It doesn't check for this header. Check out this page for detailed look into the different boot roms: http://www.smspower.org/Development/BIOSes As for the palette on SMS, it is believed that is no way to change those colors, but who knows if some hard/soft hacks would permit it. ?

Maxim Site Admin Joined: 19 Oct 1999 Posts: 11272 Location: London	Posted: Wed Aug 11, 2010 8:25 am
	Short version: US and European SMSes look for a header. Japanese ones don't. GGs check for a header if they have the blue splash screen on startup. The "legacy video mode" colours seem fixed. The system totally ignores the palette in this mode. Unless there's some "back door" way to fix it, it's just impossible. Sega even went so far as to re-release some SG-1000 games with palettes adjusted to look better on the Mark III (with the bad palette); if there was some way around it I'm sure they'd have used it. My suspicion is that someone in Sega looked up the TMS9918a colour list, which looks like: Quote (Transparent) Black Medium Green Light Green Dark Blue Light Blue Dark Red Cyan Medium Red Light Red Dark Yellow Light Yellow Dark Green Magenta Gray White ...and then assigned fixed 6-bit (SMS) colours based on these descriptions (e.g. #FF0000 for Light Red), without regard to what they actually looked like on-screen. I've put a comparison here: http://www.smspower.org/Development/Palette#MasterSystemMarkIII

RetroSpark Joined: 08 Dec 2005 Posts: 438 Location: Auckland, New Zealand	Posted: Wed Aug 11, 2010 2:24 pm
	Maxim wrote I have started work on this: http://www.smspower.org/Tags/LegacyVideo SG-1000 Yie Ar Kung-Fu has been given this tag. Is this a mistake?

Bock Site Admin Joined: 08 Jul 2001 Posts: 7445 Location: Paris, France	Posted: Wed Aug 11, 2010 2:40 pm Last edited by Bock on Thu Aug 12, 2010 3:21 am; edited 1 time in total
	Paul Baker wrote Maxim wrote I have started work on this: http://www.smspower.org/Tags/LegacyVideo SG-1000 Yie Ar Kung-Fu has been given this tag. Is this a mistake? No mistake ever happened ;) (I edited the page)

Maxim Site Admin Joined: 19 Oct 1999 Posts: 11272 Location: London	Posted: Wed Aug 11, 2010 3:16 pm
	I saw "MSX Port" and didn't apply my brain to the system field... despite what I wrote on http://www.smspower.org/Tags/LegacyVideo .

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