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I'm without DECENT schematics for this thing. I'd just got 100% of success with all games I tried on it. I got rid of some chips in the schematic using
a 74LS273 (8 flipflops with clear). On the mapper of the pictue, I'm still using 74LS74 flip flops to keep the register data. Since the thing is just a
prototype, I don't think it's a problem at all ...

Tested games :

Sonic 1 (Yesss !!!!) :) (this game seems to write at the page 3 register too ....)
japanese Kenseiden
Phantasy Star
Alex Kidd in Miracle World
(This game doesn't write to FFFE, but requires that page 01 is set at frame 1, making it a bit problematic just like ALL other 128kb games.
I guess this game has that problem because it was probably made for the 315-5208 and I think that the 315-5208 is a page 3 only mapper.
This means that frame 1 will be aways locked in page 1, then there's no need to write in FFFE)
In other hand, seems like 315-5235 sets 00, 01 and 02 at power-on, on it's mapper registers. Making it 100% compatible with
any game. I made that in my mapper too. I guess Meka and all other emulators does that too, for compatibility.

Zaxxon 3D
Space Harrier 3D
Poseidon Wars 3D
Psycho Fox
Doki Doki Penguinland
Shooting Gallery (the eprom in the board.)
R-Type (Original mask rom that I removed from my socketed 315-5235 cartridge)
And some other games ...

Better yet, the prototype has 5 leds which shows the contents of the FFFF register. You're able to know in which page it's
while it's running(Just look at them, exibiting 07 in binary at the title screen of Shotting G), also four dip switches connected
to the higher address lines. It allows me to use an 512kb eprom to burn 4x128kb games or 2x256k games in a 512kb Eprom.

Vic,

I'd be most interested in building such a device. Will you continue to tweak it or is this a 'final' version? Also, will you publish 'decent' schematics for this thing (in whatever timeframe?)... Lastly, could you tell us something more about the cost for such a device?

Regards,
Steven

Quote

> Vic,

> I'd be most interested in building such a device. Will you continue to tweak it or is this a 'final' version?

Also, will you publish 'decent' schematics for this thing (in whatever timeframe?)...
Lastly, could you tell us something more about the cost for such a device?

Quote

> Regards,
> Steven

I'm still improving the circuit. I was going to publish it last sunday, but I changed it so much (optimizations, new features
and such stuff). This morning I'd just implemented the SRAM crontrol circuit and the register FFFC bits 2 and 3.

Now I have a full bank 1&2 512kbyte ROM mapper with 32kb SRAM support (2x16kbyte pages in a 62256 ram chip.)

I'm just getting the stuff ready for release. And I'm going to post it before I go out for hollydays ...
(I'm going to make a 5 days trip this wednesday)

Cya ...

Author	Message
Vic_Viper Joined: 12 Jul 2005 Posts: 55	Home made mapper - first pictures Posted: Mon Sep 04, 2000 3:09 am
Vic_Viper Joined: 12 Jul 2005 Posts: 55	I'm without DECENT schematics for this thing. I'd just got 100% of success with all games I tried on it. I got rid of some chips in the schematic using a 74LS273 (8 flipflops with clear). On the mapper of the pictue, I'm still using 74LS74 flip flops to keep the register data. Since the thing is just a prototype, I don't think it's a problem at all ... Tested games : Sonic 1 (Yesss !!!!) :) (this game seems to write at the page 3 register too ....) japanese Kenseiden Phantasy Star Alex Kidd in Miracle World (This game doesn't write to FFFE, but requires that page 01 is set at frame 1, making it a bit problematic just like ALL other 128kb games. I guess this game has that problem because it was probably made for the 315-5208 and I think that the 315-5208 is a page 3 only mapper. This means that frame 1 will be aways locked in page 1, then there's no need to write in FFFE) In other hand, seems like 315-5235 sets 00, 01 and 02 at power-on, on it's mapper registers. Making it 100% compatible with any game. I made that in my mapper too. I guess Meka and all other emulators does that too, for compatibility. Zaxxon 3D Space Harrier 3D Poseidon Wars 3D Psycho Fox Doki Doki Penguinland Shooting Gallery (the eprom in the board.) R-Type (Original mask rom that I removed from my socketed 315-5235 cartridge) And some other games ... Better yet, the prototype has 5 leds which shows the contents of the FFFF register. You're able to know in which page it's while it's running(Just look at them, exibiting 07 in binary at the title screen of Shotting G), also four dip switches connected to the higher address lines. It allows me to use an 512kb eprom to burn 4x128kb games or 2x256k games in a 512kb Eprom.

ctznkane Guest	Posted: Mon Sep 04, 2000 3:02 pm
ctznkane Guest	Vic, I'd be most interested in building such a device. Will you continue to tweak it or is this a 'final' version? Also, will you publish 'decent' schematics for this thing (in whatever timeframe?)... Lastly, could you tell us something more about the cost for such a device? Regards, Steven

Vic_Viper Joined: 12 Jul 2005 Posts: 55	Posted: Tue Sep 05, 2000 2:10 am
Vic_Viper Joined: 12 Jul 2005 Posts: 55	Quote > Vic, > I'd be most interested in building such a device. Will you continue to tweak it or is this a 'final' version? Also, will you publish 'decent' schematics for this thing (in whatever timeframe?)... Lastly, could you tell us something more about the cost for such a device? Quote > Regards, > Steven I'm still improving the circuit. I was going to publish it last sunday, but I changed it so much (optimizations, new features and such stuff). This morning I'd just implemented the SRAM crontrol circuit and the register FFFC bits 2 and 3. Now I have a full bank 1&2 512kbyte ROM mapper with 32kb SRAM support (2x16kbyte pages in a 62256 ram chip.) I'm just getting the stuff ready for release. And I'm going to post it before I go out for hollydays ... (I'm going to make a 5 days trip this wednesday) Cya ...

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