Game Raccoon - I invented a mega drive sd cart cartridge
Reply
https://www.mrdictionary.net/gameraccoon/

Image

Over the last three months I've been working on a rewritable SD card compatible cartridge for the Mega Drive, because, well, why not!

There's two pages on the Game Raccoon website:

- in the Technical Report I describe the workings of the finished Revision 0 and what it can and cannot do. It's all very staid and only describes the final cart.

- in Matt's Chronoblogical Misadventures in Game Raccoon Land I've blogified the last three months, and taken pictures of every note, sketch, design, layout and prototype so you can see how I took some paper and a mechanical pencil and ended up with my own awesome looking cartridge. :D
Impressive stuff. :)

If you ever need any little bits of MD hardware to help with testing, I've got plenty of spare bits and pieces and I send your way.
Oh wow, that's really cool!

Solid work.
Yeah, that’s great going!
That's awesome. I've only briefly looked at the site but would it be able to play ROM images?
Thanks folks :)

TheVision wrote:
That's awesome. I've only briefly looked at the site but would it be able to play ROM images?

You really did look only briefly, didn't you? :p

Quote:
What software can I use on my Game Raccoon?

My own YM2612 Instrument Editor with graphics by Aly James allows you to explore the sounds the Mega Drive's YM2612 sound chip is capable of producing.

Over fifty homebrew Sega Mega Drive games are listed on Sega Retro, with many of them being offered as free downloads. Of course, any original Mega Drive games you purchase from sites such as itch.io that require a Mega Drive emulator ought to work. More new games for the Mega Drive / Genesis are being released every month, these are tracked on release sites such as pdroms.de.

There are many demo productions (free running animations showing novel video and audio effects) such as Overdrive by TiTAN.

The retail games Zero Tolerance by Technopop (as well as a prototype of the sequel), and Wiz 'n' Liz: The Frantic Wabbit Rescue are offered free to download from their original authors.

On the Steam Workshop page for Sega's own 'SEGA Mega Drive & Genesis Classics', over 2,474 items are available for download at the time of writing. You can find your purchased Workshop mods in X:\Games\Steam\steamapps\workshop\content\34270\; these files should be Raccoon-compatible.
devilman wrote:
Impressive stuff. :)

If you ever need any little bits of MD hardware to help with testing, I've got plenty of spare bits and pieces and I send your way.


Don’t suppose you have a controller? I recently acquired a mega drive and mega cd but can’t test it without a pad.
I can heartily recommend these if you want a brand new one.
Dr Zoidberg wrote:
devilman wrote:
Impressive stuff. :)

If you ever need any little bits of MD hardware to help with testing, I've got plenty of spare bits and pieces and I send your way.


Don’t suppose you have a controller? I recently acquired a mega drive and mega cd but can’t test it without a pad.


Attachment:
IMG_20200210_214806.jpg


I think I can arrange that :) If you've not already bought the new one recommended by TheVision, just PM me your address and I'll get one tested and popped in the post to you.
Holy moly. That's a lotta plastic ! :D

Do you have any 6-button compatible pads? I only have a 3-button pad.
Will this one do? Just tested it and it works fine. :)

Attachment:
IMG_20200210_221521.jpg
devilman wrote:
Dr Zoidberg wrote:
devilman wrote:
Impressive stuff. :)

If you ever need any little bits of MD hardware to help with testing, I've got plenty of spare bits and pieces and I send your way.


Don’t suppose you have a controller? I recently acquired a mega drive and mega cd but can’t test it without a pad.


Attachment:
IMG_20200210_214806.jpg


I think I can arrange that :) If you've not already bought the new one recommended by TheVision, just PM me your address and I'll get one tested and popped in the post to you.


Excellent, ta.
Thank you very much Devilman! :D arrived this morning. It's going to come in very handy for testing the next revision of GR as well as testing the Ocelot system.
Glad to be of help :)
devilman wrote:
Will this one do? Just tested it and it works fine. :)

Attachment:
IMG_20200210_221521.jpg


What does the 'auto' setting do?
https://segaretro.org/SG-18

According to this photo of the back of the box, TURBO is for autofire while the button is held down, AUTO is for autofire 'hands free'.

Image
Great work mr D

I don’t suppose you’re going to mass produces them?
MrD wrote:
Thank you very much Devilman! :D arrived this morning. It's going to come in very handy for testing the next revision of GR as well as testing the Ocelot system.


Yep, this. Thanks Devilman.
romanista wrote:
Great work mr D

I don’t suppose you’re going to mass produces them?

Probably not ^_^; the component cost for one of these guys comes to something like $18-$25. There's no way I could get it that much cheaper than Everdrives and so on, and those carts support savegames and mappers and things. (My cart won't ever play Pier Solar or Super Street Fighter II The New Challengers since they're too big.) I don't know how much cart shells cost. It would probably be easier for me to buy fifty or a hundred 'replacement cart shells' from some retro shop, put GRs inside them and that's that (except for the SD card slot...).

I'm not sure what I'm going to do when I get the cart working. It's more of a portfolio piece than anything. I was thinking of putting it all under agpl3 license so anybody can do what they want with it as long as they give out the source. I'm not too fussed about chinese clones, since these things already exist, and considering I'm getting it made in China that horse has already bolted.

When they're finished I'll see how much everything would be.
Image
Doesn't go below £22.40 (which makes sense since that's pretty much the component cost of one cart modified by PCBWAY's markup). Way too much to be messing around - if someone's making them it won't be me.
Ah,you already thought about production more than 90% of all kickstarters:)
romanista wrote:
Ah,you already thought about production more than 90% of all kickstarters:)

Bwahaha :p

Well I'm terrified of disappointing anyone, so I wouldn't want to get their hopes up without knowing exactly what's what.

The price is no great secret - the bill of materials and board for Rev 0 are on the site if anybody wanted to modify the PCB for some reason. You could upload them into pcbway or another site and get their price quote. The most expensive parts are the PIC, the Flash and SD card socket. I haven't looked into the price of other PICs, Flashes or sockets, but I guess a microsd slot would be cheaper simply because of it being smaller, and there might be a different kind of PIC that's cheaper that has the same ability. I think the Flash is cheapest for the size (since I moved it to another component for price reasons just before ordering), but it's possible that a larger Flash would be cheaper by virtue of being more common! 8 megabytes is a bit tiny for a Flash chip, whereas you can imagine 256/512 megabytes being included in all kinds of things like GPSes even if they don't need it just because they're cheap.

The Chinese 'all games on one cart' carts are cheaper since they don't need to be self-programmable and they almost certainly don't include the correct voltage translators:
http://web.archive.org/web/201905251159 ... -consoles/
[quote="MrD"]https://segaretro.org/SG-18

According to this photo of the back of the box, TURBO is for autofire while the button is held down, AUTO is for autofire 'hands free'.

...pic...

Ah, thanks, I see now. I'd forgotten about the 'slow motion' buttons that basically rapid fire the start button and are shit if the pause screen has menu options.

Also, the mode button sounds mysteriously vague.
The Mode button is mysteriously vague! :)

I believe that the pad itself is supposed to pretend to be a 3-button pad if you hold Mode while the powering on the system, otherwise it acts as a 6-button pad. (This is what official pads do, iirc.)

Beyond that point, games can use Mode for whatever they like - it doesn't toggle between 3- or 6-, or anything like that. It's just another button.
MrD wrote:
The Mode button is mysteriously vague! :)

I believe that the pad itself is supposed to pretend to be a 3-button pad if you hold Mode while the powering on the system, otherwise it acts as a 6-button pad. (This is what official pads do, iirc.)

Beyond that point, games can use Mode for whatever they like - it doesn't toggle between 3- or 6-, or anything like that. It's just another button.


I never knew this! I always thought that the mode button toggled between the two modes. Interesting.
The only reason I know about what the button does is that I have a six-button pad plugged into the Mega Drive I use for testing and Ms. Pac-Man was unplayable, so I went googling for the answer.

Also, I found some instructions for the official six-button pad yesterday and it covers it too:

Attachment:
IMG_20200224_091320.jpg
TheVision wrote:
MrD wrote:
The Mode button is mysteriously vague! :)

I believe that the pad itself is supposed to pretend to be a 3-button pad if you hold Mode while the powering on the system, otherwise it acts as a 6-button pad. (This is what official pads do, iirc.)

Beyond that point, games can use Mode for whatever they like - it doesn't toggle between 3- or 6-, or anything like that. It's just another button.


I never knew this! I always thought that the mode button toggled between the two modes. Interesting.

The more you know! (and so on)

When you're programming for the Mega Drive, you have to do the pad reading yourself fiddling with the front port signalling and stuff. There's no magic thing inside the Mega Drive that does any of it for you. (Unlike the Amiga CD32 which actually does!) It's possible that Sega had their own libraries they gave out to developers to do this, but folks like Factor 5 who I read did a bit of reverse engineering to get their development stuff running wouldn't have things like that, so I wouldn't be surprised if there was a bit of guesswork and fiddling and sharing of code bits.

The front ports and the expansion port are fully programmable so it's possible to use them for other things, if you're bonkers and like testing players' faith in your company's electronics skills - Zero Tolerance comes with a little graphic telling you how to wire up a cable that plugs into the 2nd controller port and turns it into a console link cable for coop play.

Image
I didn't know that about Zero Tolerance. I see that someone in Australia on eBay makes and sells the adapters.

I do like quirky stuff like that. Like how Hunter-Killer on the spectrum also had link-up play too using the Interface 1.
devilman wrote:
The only reason I know about what the button does is that I have a six-button pad plugged into the Mega Drive I use for testing and Ms. Pac-Man was unplayable, so I went googling for the answer.

Also, I found some instructions for the official six-button pad yesterday and it covers it too:


what happens with ms paceman,remapping all buttons?
romanista wrote:
devilman wrote:
The only reason I know about what the button does is that I have a six-button pad plugged into the Mega Drive I use for testing and Ms. Pac-Man was unplayable, so I went googling for the answer.

Also, I found some instructions for the official six-button pad yesterday and it covers it too:


what happens with ms paceman,remapping all buttons?


I can't remember for sure as I've sold my copy and can't re-test, but I think some of the directions just didn't work. I'm not even sure if the game uses any of the buttons.

I noticed Decapattack was also mentioned as not being recommended for use with the pad and I have that to hand so I've just tried that and... er, it's fine. Not sure why it wouldn't be recommended unless there's some extra quirk on a Mega Drive 2 possibly.
I seem to recall a couple of directions on the d pad not working properly on Ms Pac-man.
I don't think I'd ever used a 6 button Mega Drive pad, so this was all new to me, and I enjoyed hearing about it.

The Sega Link cable sounds interesting and wacky.

I'm sure I've mentioned it before, and am not the only one, but I used to really quite enjoy looking at consoles and finding these mysterious ports underneath, wondering what strange potential they held. I remember the Gamecube had quite a few underneath...
devilman wrote:
I noticed Decapattack was also mentioned as not being recommended for use with the pad and I have that to hand so I've just tried that and... er, it's fine. Not sure why it wouldn't be recommended unless there's some extra quirk on a Mega Drive 2 possibly.
At a guess, I'd say it was a US-only thing...

I looked it up thread and it seems that it works fine on Mega Drives but not on the Nomad!

Quote:
I'm sure I've mentioned it before, and am not the only one, but I used to really quite enjoy looking at consoles and finding these mysterious ports underneath, wondering what strange potential they held. I remember the Gamecube had quite a few underneath...
You haven't completed your GameCube unless you've got the Game Boy Player installed underneath. :D

I always did wonder what those ports were for - I just like having lots of stuff.
MrD wrote:
You haven't completed your GameCube unless you've got the Game Boy Player installed underneath. :D

I always did wonder what those ports were for - I just like having lots of stuff.


I had the Gameboy player and the Broadband Adapter for the bottom of mine, not that I used it for online games it was just the easiest early way to play copies and homebrew (using Phantasy Star Online)
MrD wrote:
devilman wrote:
I noticed Decapattack was also mentioned as not being recommended for use with the pad and I have that to hand so I've just tried that and... er, it's fine. Not sure why it wouldn't be recommended unless there's some extra quirk on a Mega Drive 2 possibly.
At a guess, I'd say it was a US-only thing...

I looked it up thread and it seems that it works fine on Mega Drives but not on the Nomad!

Quote:
I'm sure I've mentioned it before, and am not the only one, but I used to really quite enjoy looking at consoles and finding these mysterious ports underneath, wondering what strange potential they held. I remember the Gamecube had quite a few underneath...
You haven't completed your GameCube unless you've got the Game Boy Player installed underneath. :D

I always did wonder what those ports were for - I just like having lots of stuff.


Some versions of the Mega Drive have an extra port too, the EXT port which wasn't really used for much outside of Japan it seems. It's on a few of my spares though

Attachment:
IMG_20200225_115047.jpg
TheVision wrote:
I seem to recall a couple of directions on the d pad not working properly on Ms Pac-man.


Coincidentally, I had another Mega Drive bundle arrive today that included Ms. Pac-man, so I gave it a try with the six-button pad.

To start with, only left and right work. However, if you press Y to go down or Z to go up, then the directional buttons will work for a bit after that. But then after a little while, it'll revert back. And at some point, Left didn't work either so I had to press X for that.
The latest news :)
Image
Link play Zero Tolerance being shown off on the link play special on Bad Influence s4e3 :D
Progress is progressing slowly, understandably. Just had an email from the manufacturer's engineering team asking about some anomalies in my BOM. Turns out my capacitor choices were all the wrong package (I'd mixed up imperial and metric...) and this error was even on the Rev 0 design! I can only assume they worked off the text part of my BOM and ignored the model numbers the first time, since those boards were fitted with what I intended but not what my spreadsheet indicated. I'm glad they asked before doing something unusual, but the Rev 0 substitutes worked great.
Every designer's dream - semi-psychic manufacturing! They sound like a good partner, at least.
Raccoon Revision 1 arrived earlier this week. A very friendly DHL person placed it very gently on my porch floor and walked very quickly away. Spent the week assembling the interface parts and adapting the Revision 0 program to work inside the new layout. I ordered two boards, but only one of them works. :(

But the one that works works a treat, yaaay!

https://imgur.com/a/bz1nnGw

https://imgur.com/a/Bp2RyAz

Now I've got heckloads of blogging to do, as well as starting to look for a sprite artist to hire to work on menus and things.
Game Raccoon Revision 0 + 1: Overdrive by Titan
https://www.youtube.com/watch?v=SlSrLwtQxP4

Game Raccoon Revision 1: MD-NICCC by Titan
https://www.youtube.com/watch?v=ac3Zcbfl3o8
Really nice work, Kamineko! You're a talented chappie. :)

I taught myself KiCAD a couple of months ago, just in time for the outbreak to disrupt the board house! My first design took a month to turn up, and I paid for "two day" shipping. :'(

Everything seems to be back in full swing now, though, and there's a steady pipeline of boards wending their way around the globe to me...
Thank you and Best of luck :D

I'm still trying to get a refund or a replacement for the second of my prototype boards that was manufactured incorrectly...
Image
Got myself a nice case for the Revision 1 prototype. :D I've been working on the new software and menu and stuff, and I'm up to the most difficult part... finding somebody who can draw me a nice mascot!
Wow, that is pretty cool!
I do like transparent cases, where you can purve at all of the internal furtlings... :)

I wonder if technophobic people find them off-putting, for similar reasons?
I'd have picked green, blue, grey, white or colourless if they had them but my choices were transparent red, transparent black, red or black.

Either way the transparency is essential for the blinking lights that go on while a game is being written to the cart!!

Image

I was kind of hoping the edges of the cart would light up, but I guess the plastic isn't laid out correctly for that (I think I'd have to have a plastic pillar directly in front of the LEDs for it to shine into for it to be channelled around the interior frame.

I could see folks thinking that transparent cases for things look more fragile than opaque, like a transparent Game Boy Pocket looking like it'll shatter or melt if you hold it for too long.
Page 1 of 1 [ 48 posts ]