So me and a buddy have been doing NES reproductions for a while, and have done around 15 games (mostly english translations of Famicom games). Now there's a few Genesis games we're wanting to do, but it seems to be quite a bit harder to find Genesis stuff info since it seems more people just want you to pay for a cart to be made instead of sharing information. Anyone have any pointers or suggestions to get started on Genesis?
Page 1 of 1
Good guides to get started on Genesis Repros? Experienced with NES already
#2
MathUser 
Posted 26 March 2013 - 12:34 AM
- 3rd top wiki contributor
-
- Posts: 1902
- Joined: 09-November 05
- Gender:Male
- Wiki edits:14,865
00
Sonic 2 classic heroes would make a good cart, even though it might not be at final revision yet. If you make a cart of it, make a note of the version on the label. So you'll know if you need to make another cart later.
#3
GerbilSoft
Posted 26 March 2013 - 09:41 AM
- RickRotate'd.
-
- Posts: 2223
- Joined: 11-January 03
- Gender:Male
- Location:USA
- Project:Gens/GS
- Wiki edits:158
9001
For MD cartridges, you will need the following:
Cartridge pinout is available at http://www.gamesx.co...s/gennycart.htm .
It's a pretty straightforward connection: Connect the address lines on the cartridge slot to the corresponding address lines on the EPROMs. (A01 on the cartridge slot maps to A00 on the EPROMs. For 1x16, all 16 data lines map as-is; for 2x8, map D00-D07 to the "low" EPROM, and D08-D15 to the "high" EPROM. Also make sure you connect the !C_CE and !C_OE lines to the corresponding chip-enable/output-enable lines; otherwise, you will end up with either nothing on the data bus, or bus conflicts when accessing non-ROM areas.)
You'll also need to short pin B32 (!C_DTCT) to ground. (Most official cartridge use a capacitor for this, so you may want to check a retail cartridge for reference.) This maps the cartridge to $000000; if left unconnected, the cartridge is mapped to $400000.
Retail PCBs also seem to have a resistor connected somewhere; I'm not sure what this is for.
That's pretty much it for a basic ROM-only cartridge. SRAM takes a bit more work, and you may have to add some flip-flops if your ROM is larger than 2 MB. (I'm not sure how SRAM is wired to the cartridge, so you'll need to check e.g. the Sonic 3 PCB schematic or something similar.)
- 16-bit or 2x8-bit EPROMs and/or NOR flash chips
- 64-pin (2x32) PCB
Cartridge pinout is available at http://www.gamesx.co...s/gennycart.htm .
It's a pretty straightforward connection: Connect the address lines on the cartridge slot to the corresponding address lines on the EPROMs. (A01 on the cartridge slot maps to A00 on the EPROMs. For 1x16, all 16 data lines map as-is; for 2x8, map D00-D07 to the "low" EPROM, and D08-D15 to the "high" EPROM. Also make sure you connect the !C_CE and !C_OE lines to the corresponding chip-enable/output-enable lines; otherwise, you will end up with either nothing on the data bus, or bus conflicts when accessing non-ROM areas.)
You'll also need to short pin B32 (!C_DTCT) to ground. (Most official cartridge use a capacitor for this, so you may want to check a retail cartridge for reference.) This maps the cartridge to $000000; if left unconnected, the cartridge is mapped to $400000.
Retail PCBs also seem to have a resistor connected somewhere; I'm not sure what this is for.
That's pretty much it for a basic ROM-only cartridge. SRAM takes a bit more work, and you may have to add some flip-flops if your ROM is larger than 2 MB. (I'm not sure how SRAM is wired to the cartridge, so you'll need to check e.g. the Sonic 3 PCB schematic or something similar.)
This post has been edited by GerbilSoft: 26 March 2013 - 11:27 PM
Reason for edit: !C_CE and !C_OE.
Reason for edit: !C_CE and !C_OE.
Page 1 of 1