188 Replies

The page is password protected πŸ™

Sorry about that. I had changed everything to “Public” in the privacy settings but somehow the changes didn’t get saved.

The link should be working now.

My favorite part of this idea is how its not going to use donor carts…

nobody would wish Virtual League Baseball to be $50 someday, right? πŸ˜€

Sounds amazing !

I’ve had fun making the FlashBoy carts, but with this cart on the horizon it is pointless for me to develop it any further or manufacture more of the current design.

I look forward very much to using an SD card based cart on the VB :thumpup:

First progress update is up. All future progress update will be posted directly to this page:

http://brennanthl.wordpress.com/

What are you using to case the cart (if you’re not using a donor cart) ?

I’m up for suggestions on that one. I know some members here have 3D models of the case but it would be expensive to have them made and I don’t know much about case design. For now I’m more worried about functionality and getting the right connector. I was toying with the idea of not using a case at all and putting a conformal coat over the PCB to protect against ESD and sharp edges. And then I would put spacers on the board so it fits correctly against the VB, and add a hand grip at the end for removing the cart from the system. The VB community is pretty sophisticated anyway so I don’t really have to “childproof” the cartridge.

I don’t really have to “childproof” the cartridge.

It’s beyond this groups finances to get a mould made. Having them milled is too slow / expensive / poor finish. And un-cased is just crap :thumpdown:

There must be an ‘off the shelf case’ somewhere which can be hacked to fit.

On the Vectrex, we used adapted Intellivision cart cases (before Sean Kelly dropped the 20K to get them moulded).

  • This reply was modified 10 years, 9 months ago by MineStorm.

Does anyone have the dimensions for a (original) gameboy cartridge off hand? I know it’s not the same as a VB cart but they are plentiful and I could potentially hack it and try to make it work. I personally don’t care about having a case for the cart, but I understand it’s an issue that needs to be addressed.

When you get to the time where you need a case, I can help you make the carts by hand. The biggest downside is it takes basically 1 day to make a mold and 15 – 30 minutes to cast a part, and it all has to be done by hand. But the advantages are most of the time you don’t have to do anything other than wait, your only hardware requirement is a microwave, and for one off parts it is relatively cheap (probably $5 to $10 per cart). Plus, you can make any color you want (even metallic colors like silver and gold, or transparent colors)

The easiest way to do it would be to cast the case right over the PCB, which would mean after it was cast, you could no longer get to the pcb. Yes I understand the needs of SD card access, this wouldn’t be a big deal. Don’t know if you would have to RTV the board or not.

I guess my biggest concern is that in my view, there is no way you can beat the flashboy price. Best you could probably do is match the price. Your pcb will be at least the same size, your carts will cost at least the same amount, and you have the same amount of parts to buy and solder onto the pcb. So where are you going to save money?

If you check my project page at http://brennanthl.wordpress.com/project-vboot/

you will notice I did not mention anything about price. I am not very concerned with that right now, because there are many other things I need to figure out at the moment. My guess is that the final design would [unfortunately] not be much cheaper than the Flashboy, and here is why:

1) Board cost. Can’t get around this. If I make a huge order of boards than the per-board cost goes down but this requires that there is enough interest/demand such that I can unload all/most of them
2) Memory costs. A 32M SRAM costs about $36 for a single part, and a 16M SRAM costs $22 for a single part, for the parts I’m currently looking at. These will go down if I order in bulk of course, but again, I’m just a college student and I don’t really have the resources to order parts in large quantities in the near future.
3) Processor and other component costs. SD card will probably cost about $5-10 depending on the size
4) VB connector, which will probably end up costing about $8 each
5) VB cart case, which is up in the air as far as cost goes

Now, as for additional charges on top of the above, I wouldn’t do that. I would sell the cart for what it cost me to build, plus a little more to cover packaging, shipping, extraneous build costs, time spent assembling, etc. I’m not looking to make much money on this thing, I have a day job for that. πŸ˜€ Unfortunately for us, the hardware required in such a device is fairly rare and by no means inexpensive. There are just certain price restrictions I can’t get around.

Well, it’s safe to say this is the single hardest 2-layer PCB I have ever made. It’s so incredibly dense I can barely even tell where everything is now. I still have a few sections that are causing problems but as you can see, progress is being made.

Vaughanabe13 wrote:
Does anyone have the dimensions for a (original) gameboy cartridge off hand? I know it’s not the same as a VB cart but they are plentiful and I could potentially hack it and try to make it work. I personally don’t care about having a case for the cart, but I understand it’s an issue that needs to be addressed.

No dice, VB cartridges are way thinner than GB carts. In fact, VB cartridges are just about the thinnest carts I can think of. You can fit a VB cart inside a Game Gear cart carrying case, unfortunately you have to rotate it 90-degrees so that wouldn’t work either. (Plus the fact that Game Gear carts are getting to be somewhat of a rarity too.) Personally, I’d be fine with a bare PCB, but from MineStorm’s comment, I would guess that that isn’t true for everyone else.

On a side note, I didn’t notice this thread when you posted it, really nice work dude. I probably wouldn’t be able to afford this any more than a FlashBoy (or an EPROM cart for that matter) but I was always wondering, “How would you go about making an SD cart?” I’m glad someone has the engineering skills to get it done. What are you getting your degree in?

Well, it’s safe to say this is the single hardest 2-layer PCB I have ever made

You are a masochist. I could have put it through my copy of Electra for you.

Fwirt wrote:

Vaughanabe13 wrote:
Does anyone have the dimensions for a (original) gameboy cartridge off hand? I know it’s not the same as a VB cart but they are plentiful and I could potentially hack it and try to make it work. I personally don’t care about having a case for the cart, but I understand it’s an issue that needs to be addressed.

No dice, VB cartridges are way thinner than GB carts. In fact, VB cartridges are just about the thinnest carts I can think of. You can fit a VB cart inside a Game Gear cart carrying case, unfortunately you have to rotate it 90-degrees so that wouldn’t work either. (Plus the fact that Game Gear carts are getting to be somewhat of a rarity too.) Personally, I’d be fine with a bare PCB, but from MineStorm’s comment, I would guess that that isn’t true for everyone else.

On a side note, I didn’t notice this thread when you posted it, really nice work dude. I probably wouldn’t be able to afford this any more than a FlashBoy (or an EPROM cart for that matter) but I was always wondering, “How would you go about making an SD cart?” I’m glad someone has the engineering skills to get it done. What are you getting your degree in?

Yeah, I finally got a calipers and measured the GB cartridge so I know what you’re talking about. Plus my board has to be bigger than the area of a GB cart anyway because of all the traces. The biggest physical-size problem I’m having right now is trying to figure out the VB connector. I have some connectors that are a very very close match, but they aren’t thin enough. So I have to sand away some of the plastic, but that weakens the integrity of the connector, and it also doesn’t have the two raised grooves that the VB cart does, so it might make insertion hard. I mean, theoretically once you put this cart in your VB you should never have to take it out (just the SD card, which can be easily popped out), but I can’t rely on that because some people will be using it on multiple VBs and may be inserting/removing it often. As far as the bare pcb goes, I’m afraid people have been spoiled by the great work Minestorm has done on the Flashboy and using donor carts. At this point I don’t think my cart will even fit inside a VB case, because I have to put components on both sides of the PCB, which increases the thickness.

Affordability is always going to be a problem with this kind of cart, unfortunately. The VB technology is really old and the components are rare and expensive. The board costs won’t be so bad if there is a high enough demand, because I can make large batches of PCBs and get a discount that way. It all depends on how many people are interested in something like this. I can’t imagine I would be able to make this cart any cheaper than $60-70 USD but it’s tough to say. Again, I don’t care about making a profit or anything. I might even put the designs and firmware out there for DIY people who want to order their own board and components.

Thanks man, I appreciate the compliment. I’m currently finishing my last semester of undergraduate work, so I’ll be graduating in December with a Bachelor’s of Electrical/Computer Engineering. After that I’ll probably get a Master’s through my company, but I haven’t decided what I want to focus in.

MineStorm wrote:

Well, it’s safe to say this is the single hardest 2-layer PCB I have ever made

You are a masochist. I could have put it through my copy of Electra for you.

Haha, I guess I am. πŸ˜€

Electra looks like a pretty cool autorouter. I tried the demo version and it worked fairly well (only missed like 20 or so connections on a 2-layer board). The problem is you can’t export anything with the demo version, and I don’t have $130 to spare for a license.

Vaughanabe13 wrote:

Affordability is always going to be a problem with this kind of cart, unfortunately. The VB technology is really old and the components are rare and expensive. The board costs won’t be so bad if there is a high enough demand, because I can make large batches of PCBs and get a discount that way. It all depends on how many people are interested in something like this. I can’t imagine I would be able to make this cart any cheaper than $60-70 USD but it’s tough to say. Again, I don’t care about making a profit or anything. I might even put the designs and firmware out there for DIY people who want to order their own board and components.

Open source really is the way to go. I like how the PVBCC is going open-source this year so we can all learn how the pros do such cool stuff ;-). Actually, I’ve always wished for schematics of the FlashBoy, just to see how it works and if I could make a clunky similar solution. I’m a computer science student (who wishes he could’ve studied computer engineering πŸ˜› ) but I do some hardware hacking as a hobby, so I’ve played with microcontrollers, nothing as professional as that board layout you’ve got there though.

And I can’t believe you don’t want any profit, at least throw $10 into the total cost for yourself, man.

+1 to making the hardware open.

+1 to including some profit in the price (so you have more starter cash for other projects ;-))

Also, great job on the manual routing! That was 1000x faster than I could have done it (at least!) :-D. I think too much automation can be a bad thing. It’s good for people to practice doing stuff the “old fashioned way” πŸ˜‰ Although, if I could afford it, I’d probably use that fancy auto-router πŸ˜› The AR in Eagle, even as limited as the free version is, is a big help.

Did you actually route that all by hand? A lot of that looks very random, like an auto-router would do. Of course that probably happens when you’ve got lots of chips with pinouts that don’t exactly line up πŸ˜› . And I disagree about using the auto-router… all the ones that I’ve used have sucked, and even if they do route, they look like crap πŸ˜‰ .

I mean… compare: http://www.planetvb.com/content/hardware/flash_carts/flashboy/images/fb_proto1_1.JPG with http://www.planetvb.com/content/hardware/flash_carts/flashboy/images/fb_proto4_2.JPG . I guess Richard could probably answer this… but the first one DEFINITELY looks auto-routed. Was that Electra? The second one looks possibly auto-routed but seems to have at least some manual routing (or maybe just some better auto-routing rules).

DogP

DogP wrote:
Did you actually route that all by hand? A lot of that looks very random, like an auto-router would do. Of course that probably happens when you’ve got lots of chips with pinouts that don’t exactly line up πŸ˜› . And I disagree about using the auto-router… all the ones that I’ve used have sucked, and even if they do route, they look like crap πŸ˜‰ .

I mean… compare: http://www.planetvb.com/content/hardware/flash_carts/flashboy/images/fb_proto1_1.JPG with http://www.planetvb.com/content/hardware/flash_carts/flashboy/images/fb_proto4_2.JPG . I guess Richard could probably answer this… but the first one DEFINITELY looks auto-routed. Was that Electra? The second one looks possibly auto-routed but seems to have at least some manual routing (or maybe just some better auto-routing rules).

DogP

I let the Eagle router do its thing first (mostly cause I was just curious what it would do) and it only filled in about 10-15% of the traces. Then from there I modified some things and did the rest by hand. Probably took me 20 hours or so but it has still changed a lot since then. I got “in the zone” for a while at night, ended up staying up most of the night working on it. I agree it looks pretty bad and random. The problem is I would try running lines and almost immediately come across a trap, so I ended up having to use probably 2x more vias then I wanted and the traces are crossing each other all over the place. It’s so hard because as you know, there are several shared buses, and the pins of the SRAM are REALLY random and don’t follow any kind of logical order on the footprint. The PCB has changed quite a bit since I posted that screen, it’s an ongoing process.

 

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