SMS direct to Genesis

Ask anything your want about Megadrive/Genesis programming.

Moderator: BigEvilCorporation

Post Reply
Jazzmarazz
Very interested
Posts: 60
Joined: Wed Mar 12, 2014 11:11 pm
Location: Michigan
Contact:
Contact Jazzmarazz

SMS direct to Genesis

Post by Jazzmarazz »

Hi there, Im trying to get a simple 32Kbyte SMS ROM to run directly on the Sega Genesis.
From what I understand, I need to ground B30 (!S_RESET) and if I want support for the pause button, I will need to connect B9 to VCC, B10 to GND and Pull B11 high, with a button connected between it and GND. This is based on Raphnet's schematic for a pass through cart from SMS 50-pin to 64-pin SMD here. And also based on my probing of an official SMS cartridge.

Here is my schematic that I am not sure of.
Image

I was trying to make a test cart.... but realized only my Genesis 3 and Nomad are working right now...

Does anyone have corrections for my schematic?
Top
Jazzmarazz
Very interested
Posts: 60
Joined: Wed Mar 12, 2014 11:11 pm
Location: Michigan
Contact:
Contact Jazzmarazz

Re: SMS direct to Genesis

Post by Jazzmarazz »

I have gotten it to work, but only partially. It took so long because I had to enable SMS mode on my Nomad which was a nightmare.
In any case, The program runs and sounds fine but the graphics are glitched. Some pixels repeat, and everything is very faded out.

Is this a problem with RAM/VRAM? Do I have a bus conflict with my OE and CE configuration?
Top
Post Reply

Return to “Megadrive/Genesis”