Internal flash cart *UPDATE: New idea, need help!*

[Zeon]

UPDATE: So I got to talking with one of my friends about this whole internal flash cart business, and he gave me an excellent idea, why not use CompactFlash cards or similar?

CF cards have a mode where the basically act like memory, perfect for storing rom data, plus they have access to anything you would need to be able to connect and use it via it's pinout. So what I plan to do is either one of two things: Build a hucard that has a cf card port built in, or hardwire in a cf card port in the system. The idea would be simple enough, use some software like WinHex to write the binary data of a rom onto the card (ie no file system). pop it in the installed cf card port and away you go.

Here is what i need help with and info on:

1. Programming a rudimentary menu and rom loader for multiple rom support.
2. Now this is the ambitious part: cd rom games on the cf card. I know this would require at the very least programming a custom system card bios that knows to read from the cf card and probably a lot of reworking to get the audio to load from the cf card. Couldn't you rip the binary data of the audio and write code in the custom system card to read it from the cf card? I want to know how feasible this would be.
3. Building on the cd rom support would it be possible to use part of the cf card's memory as the extra ram of the system card 3.0 and arcade cards? I'd imagine the problem here being the speed of the cf card, anyone know if this is feasible either?

Duo is already graciously donating a 32 mb CF card for experimenting. If anyone knows where i can get two cf card readers for next to nothing (ie < $1), one just needs to have the port intact and does not need to work, or if anyone is willing to donate that would be great too. Most of all I need good info on the questions asked, and if anyone into PCE/TG-16 coding is willing to help with the rom loader or custom system card bios that would be greatly appreciated.

End update


So I was up late last night chatting with duo and oldskool, and at some point we talked about the unused spot for a flash chip or whatever that was rumored to be a built in game but later got scrapped in the final design of the tg-16.

I got to thinking, how cool would it be to solder in a socket to the bus and install flash memory, and make essentially an internal electronically erasable/rewritable flash cart. Obviously you can't just solder in a socket in the blank silkscreened place even if you get the same rom package type, as the pinout for a sizable flash memory will undoubtedly differ. However you can solder in a socket with wires going directly to the bus via the hucard slot pins.

The theory is simple, all a hucard is is a rom with a edge connector to interface with the pce/tg-16 bus. In a few rare cases some extra ram or a battery however that is outside the scope of this mod. So I went ahead in this venture and for the time being soldered a socket up to the bus to match the pinout of a 27c801 8 megabit 8 bit eprom. I had already done a region mod,  so for the 8 data lines I tapped the bus from elsewhere on the board, in my case one of the other unused silkscreened spaces for some sort of ic. I just matched the pins of the eprom to the lines that the bus expects to receive each signal from, and soldered the wires to the proper places.

I burned the eprom with Jackie Chan's Action Kung Fu us rom, stuck it in the socket, reassembled, and bam the game booted right up.

This is just the beginning as there are some obvious flaws with my current mod:
1. With a eprom I will need to disassemble the tg-16, remove the eprom, and erase it in a uv eraser every time i wish to reprogram it. This is both tedious and time consuming.
2. If an eprom is present in the socket eprom (ideally a game or demo) and I want to play a original hucard, I can't as the bus will be data from both the eprom AND the hucard which will result in garbage code and just end up confusing the cpu. To get around this the eprom would have to be removed from it's socket (again involving disassembling the tg-16....).

When I get some more free time here is what i propose as a final design:

1.  At least 8 Megabits of flash based memory (big enough to hold any commercially released game; one at a time), for quick and efficient erasure and programming.
2.  Usb interface installed in the tg-16 for fast reading and writing speeds compared to a parallel port.
3.  Simple Pc software to read and write roms to the internal memory via usb.
4.  Switch to change the program/game source, either the hucard slot or the flash chip.

Possible features
1. A loader menu for multiple games (flash memory would be of a bigger size then).
2. Hardware and software to backup both legit hucard games and contents of a Tenokoe bank and file cabinet on applicable systems and add-ons.
3. Extra ram found on system card 3.0 and arcade card pro/duo

Obvious advantages would include no longer needing a region mod/converter or grounded pin on pce systems to enjoy truly region free gaming. It would work on all pce hardware, permitting space. You would have the ability to run non commercial roms just like any flash cart and it can be used to debug code for those looking into pce programming. Lastly the one big advantage this should have over similar solutions, ie neo flash and tototek flash carts is the price point. Looking strictly at the price of parts, it's a fraction of the cost, the main cost would come about from the labor of installing the necessary parts.

It certainly wouldn't be for everyone, but I think it's a cool idea nonetheless, in fact I am surprised that no one else has done something similar, or if they have I couldn't find any evidence of it.

I need to take some pics to illustrate the process, though imo if you can solder and understand the basic theory behind the mod, it's pretty straightforward. In any case I don't have a access to a camera at the moment; I will post pics as soon as I can take em.

[chop5]

fantastic idea  the gods favor the bold. almost limit less possibilities. This could be the last great rebirth of an old console

[agt_dale_cooper]

Jesus, I'm on board.
Will follow this progress intently.
Thought from left field:  Screw the cost, hard wire a Tototek/equivalent to motherboard, epoxy USB interface to outside.
Better yet, convert USB to Ethernet, get something that assigns IP, be able to delete/upload ROMs from your TG/DUO/WTFE like you can FTP with the original Xbox [which is ironically where I play most of my TG16 shit anyway, BUT....]
Zeon, you look like you know your shit here...got anybody that can cheaply CLONE a Tototek?  Removing the HuCard pins/assembly would reduce cost, perhaps there are other things that could be removed from it's build as wel....you COULD hardwire this thing directly to the board (with power/ground/etc), and theoretically if NO ROMs were present on the flash memory, it would boot any HuCard stuck in it's slot....right?
I'm sure I've got this comically oversimplified, but it's something to at least ponder....right?
[Hello, chop5, great quote, 'the gods favor the bold'....]

[Zeon]

Yeah i was thinking a blank flash chip wouldn't interfere with normal hucard play. I really want to test it first though. Replicating a tototek isn't all that hard since essentially all it is, is some flash memory and a usb/parallel port interface that plugs into the hucard slot

Really they kinda have the market cornered as the only competition to the tototek tg-16/pce flash cart is the neo flash or whatever it is called and I have heard it is dodgy at times. As such, that is the main reason for the jacked up price, because they are essentially the only game in town.

Another idea I was kicking around was installing the flash chips internally and making a usb interface hucard. But if I am going to the trouble to make a hucard why not integrate it all in one card like the tototek?

Getting some custom hucard type boards manufactured will be the main problem. Unless I printed small quantities of pcbs myself (very time consuming) I would have to find a manufacturer and I can guarantee you unless i had a large guaranteed interest it will be costly.

I really don't want to go that route though, due to the trouble and $$$ involved, modding a system internally would be time consuming but a lot cheaper and less trouble in the long run.

I do realize most would like a nice affordable plug n play flash cart for their pce, however this is more of a personal project, I will likely only do a few for myself and maybe for some friends. The only way I would get flash carts manufactured is if I get gobs of free time, a lot of interest and have money to invest. Which will probably not happen anytime soon. I am doing this more for the enjoyment I get out of doing it, I'm not really interested in making mass amounts of money off of it.

I will keep you posted on the progress, though I have a lot of other things i need to focus on before going further into this project.

[quoth09]

Wow...awesome work there. I was not even aware of any spot on the system like this, otherwise I would have thought about doing this in the future myself. Why hasn't anyone else done this before?

Pretty much like agt_dale_cooper said:
If anything, if you don't end up making some kind of device with that, it would be simple to just makeshift your own: run lines from the spot, and mount a socket adapter on that worthless flounder of a port cover (or anywhere on the system case that is empty for that matter), and put the eeprom there, or some other kind of device that can be read by that method. Also, throw a switch in the works to where if you don't want to pull out the chip, the system can still be booted by HuCard.

Anyone happen to know if there is a spot like this on any of the PC Engine units? I'm guessing no.

[NecroPhile]

It sounds pretty dang interesting, though a bit impractical for the technically retarded (like me).  Could this contraption be kept external and connect to the system via the HuCard slot?  A damaged HuCard (or some piece of crap like Timeball) could be sacrificed for the edge connector, and then it'd be portable and easy to use with multiple consoles or with an Express.  Anywho, please keep us updated on the project's progress.

1.  At least 8 Megabits of flash based memory (big enough to hold any commercially released game)

No love for SFII, eh?

Obvious advantages would include no longer needing a region mod/converter or grounded pin on pce systems to enjoy truly region free gaming.

How's that, via hacked roms?  Wouldn't booting a real HuCard or unmolested rom still be problematic?

[Zeon]

It sounds pretty dang interesting, though a bit impractical for the technically retarded (like me).  Could this contraption be kept external and connect to the system via the HuCard slot?  A damaged HuCard (or some piece of crap like Timeball) could be sacrificed for the edge connector, and then it'd be portable and easy to use with multiple consoles or with an Express.  Anywho, please keep us updated on the project's progress.

Yes it could be made external fairly easy, however I don't know how useful that is for the average joe seeing as you will still need an eprom programmer to be able to erase and write to it. Unless you meant add the usb connectivity to the card itself. Essentially what you described is a homemade flash cart. Also, as crappy as games like Timeball are, I can't bring myself to destroy a game if I can help it.

1.  At least 8 Megabits of flash based memory (big enough to hold any commercially released game)

No love for SFII, eh?

D'oh, for some reason I thought the 20 Mbit thing was incorrect, after looking at the rom size, it does indeed seem it is correct. (I knew there was a reason for the "preggo" card) Either way the extra space needed for SFII would not add much cost, as we are still talking about pretty small sizes of flash based memory.

Obvious advantages would include no longer needing a region mod/converter or grounded pin on pce systems to enjoy truly region free gaming.

How's that, via hacked roms?  Wouldn't booting a real HuCard or unmolested rom still be problematic?

On a US turbografx, no as it understands encrypted and unencrypted games. You are right, US roms would need to be decrypted before they would play on pce hardware, I did not mention this as the tools to decrypt them are readily available all over the internet, and easy to use. Yes original games still need the region mod and/or grounded pin, but when you have writable memory to write any game you pleased onto it, I'd imagine that not being too problematic, as I would think hacking the rom is a lot less trouble than doing a region mod. Then again the types of people able to do this kind of work would have no problems with a region mod.

[spenoza]

Is the TG the only system with room for something like this? I imagine the PC Engine Core is right out, eh?

[Zeon]

Is the TG the only system with room for something like this? I imagine the PC Engine Core is right out, eh?

It may be possible, I'd have to open up my Core to see, but from what I understand it's pretty darn compact in there. Basically if you can fit a flash chip and some wire anywhere in the case, it should work. Though a socket is likely out of the question. (Not really needed if you install a usb/parallel interface)

[Zeon]

Bump for an update, see first post. 

[Duo_R]

I found the 32mb card, u just need to find a reader!

[SignOfZeta]

I would pay a solid $200 for a Flash HuCard that actually works, but it must have the following attributes:

It must use standard off the shelf memory cards, SD, Compact Flash, whatever.

It must use USB, none of this serial/parallel port BS.

Here is the hard part: it must be drag and drop. I can't be bothered to run some non-functional POS software that hates my memory card reader, or my motherboard, or my OS, or whatever. What I want is something like R4, Cycle DS, etc. What I don't want: Tototek.

I'm hella psyched for the right stuff, but completely not interested in the sort of PCE flash solutions we've seen so far out there.

That CDROM2 emulation sounds really REALLY cool, but also quite hard to do. I don't need anything that awesome, I just need an R4 for my PCE.

Building it into the system is a neat idea in theory (imagine a Core Grafx with multiple GB of CDROM games built in and no moving parts other than the power switch!) but really I'd rather have a HuCard interface since I can transport stuff from one system to the next.