Making SEGA Genesis cartridges

[pbj]

A couple of updates.  It was time to add stereo out on the back of the Genesis 1. 

You buy a headphone extension cable for 50 cents and cut off the female end.  Then you fish the severed wire through the unused hole on the back of the case.  Still unsure what the heck that thing was for, it's on the Genesis 2 as well.  Added a zip tie for some amount of protection.



This didn't photograph so well, but the L channel wire goes to pin 1 of the Sony CXA1034 amplifier chip, the right channel to pin 8, and then you can pick up ground anywhere on the PCB.  Or pin 13 if you insist on jumping another wire onto the amplifier.  Anyway, this gets you a clean pre-amp signal almost directly off the YM2612 sound chip without interference from the headphone port.   I opted to tie into the sound chip ground pin.



Then you seal it all back up and here you go:




In other news....

Somehow my AliExpress order of "5 32X cartridges x 4" got converted into 4 cartridges.  Still got charged for 20, though!  So we're in the dispute process, but here's what I got:



It's the usual Genesis flashcart and works with the Genesis flashcart flasher, but it does have the wider 32X hole pattern.



Lesson learned here was I would be very, very careful spending any kind of real money on a 32X cartridge you can't open up and verify yourself.  The shell is dead on accurate to the real thing and the overall weight is comparable. With a high quality label, it would be very difficult to tell the difference.


 

[Malenko]

So we're gonna make a buncha spiderman Web of Fire carts?

[Manu25]

Let me introduce myself: my name is Manuel, and I'm passionate about retro hardware, especially the Sega Genesis/Mega Drive. I've been researching the creation of homebrew repros and cartridges for some time now, and I decided to join this forum because I see a very active and knowledgeable community on the subject.
I tried to create a functional Sonic Hellfire Saga with save but couldn't, and after Googling, I ended up here. I hope you can help me.
Thanks in advance.

[pbj]

Howdy, Manuel, nice to see someone interested.  I posted the art files and the PCB here:

https://forum.arcadecontrols.com/index.php/topic,164992.msg1777919.html#msg1777919

Malenko put together the nice looking art package.  One resides in the World's Largest Sonic the Hedgehog Collection outside of Houston.

That's the revised gerber file that resets the FRAM or whatever chip appropriately.  I still chuckle that nobody noticed in six years that it wasn't working correctly.  Author claimed it was fine on PAL consoles.  Bill of materials was about $12 a cart last time I made one.  That cartridge also works with a lot of the newer homebrew made with SGGK - I don't think I ever got it reliably saving with Gun Slugs, but Cave Story, Sonic Complete, and Rocket Panda were fine. 

[Manu25]

Hi friend, THANK YOU for sharing the file with us and the arts, I will convert it to PAL SEGA MEGA DRIVE.

I have a question about this. I'm trying to order the boards from jlcpcb, but I've noticed that the drills on the board don't appear in the viewer, while they appear correctly on other boards I've ordered previously. I've attached an image. Is this correct?

[pbj]

It should have holes.  I ordered mine from PCB Way and had no issues.  In fact, I uploaded the exact same file here that I uploaded there.  Make sure you solder those 322 jumpers before you populate the board or you're going to have an annoying time.


Maybe Malenko can post the PSD files so you can convert his artwork to the PAL layout?

[Manu25]

Thank you again, I ordered. I'll tell you if I can get them to work, thanks.

[Manu25]

@pbj just received the boards and all components and yeah!!! it works perfectly, thank you very much. Now i will make the pal cover, when finish I will publish it here.