FDSSTICK on twin famicom

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FDSSTICK on twin famicom
by on (#213326)
Hi, I recently bought myself a twin famicom AN-500B and to complete my setup I wanted to ad a fdsstick to it.
My end goal is getting a setup in which I could rewrite faulty disks if I encounter them.

Following advice of others I so far bought the fdsstick, a ram adaptor and the 2 IC's (74LS45 & 74LS76) to mod the board for write protection.
But to be honest, the help and info given is sparse.

Could someone clearly tell me what my options are and what the minimum is that I need for a setup.
Some questions come into my mind like:

Does the 2 IC mod work with the fdsstick, or do I need a mod chip?
Can I write disks if I use the ram adaptor?
What cable is needed to write disks?
And how can I get such a cable in Europe?

Lastly:
If I get my setup going. Is there any tutorial explaining how to write a disk?
Re: FDSSTICK on twin famicom
by on (#213335)
Hi, this thread discusses the type of protection circuit inside of the drive itself, and also a way to defeat the copy protection circuit on the power board of the Twin Famicom: viewtopic.php?f=9&t=11342&p=129898
Re: FDSSTICK on twin famicom
by on (#213392)
Thank you for pointing me to that page.
Apparently I was into the same situation. I had the 7201 so no modding of the chip was needed. The bypassing of the powerboard was the only thing that was left to do. Because of how it was made, I managed to mod it without any soldering and completely reversible. As soon as I get everything confirmed working, I will post a guided tutorial of how I did it.

Now I'm waiting for my fdssick and I need more information on what cable to get and where to get it. I prefer not destroying old hardware but I am on a tight budget.
Re: FDSSTICK on twin famicom
by on (#213528)
Still waiting for my parts I had a better look at the FC Twin expansion bay (In other words Port C and D).
If I understand the console correctly then the 2 parts of the famicom disk system (ram adaptor + drive) are connected using the external jumper cable, effectively splitting the disk system in 2 separate units. Looking how the FDSStick is connected to a standard FC+FDS setup then I asume from the pictures that for playing roms the FDSStick is plugged into the Ram adaptor to emulate the Drive. But for writing the FDSStick is plugged into the Disk system to take control over the drive (not using the ram adaptor). Again on "http://3dscapture.com/fdsstick/" there has been mentioned that on a twin famicom you could use the ram adaptor to play games, or use the cable from a ram adaptor to connect the FDSStick directly to the twin famicom. This by connecting it to port C which is the left port. I assume that port C is the internal ram adaptor.

No other mentioning has been done about the use of the FDSStick on these systems. But if I'm not mistaking then the only way you could write on a twin famicom is to connect the FDSStick to port D (the right). Can anyone confirm this? And has anyone ever tried this?

I don't see how you could write on the system if you use an external ram adaptor since you disconnect the internal ram adaptor + drive completely.

I really hope I get full disk writing working as I will inevitably stumble on broken disks. Having a chance in being able to fix them would be golden.
Re: FDSSTICK on twin famicom
by on (#213536)
I found this post:
viewtopic.php?f=9&t=12163&p=179901&hilit=tototek#p179901

Apparently KittyFae managed to connect the FDSStick in a fully working order. But his explanation is a bit puzzling to me:
Quote:
So I finally figured out how to write to disks using the FDSStick and a Twin Famicom.
1) Make or get the normal FDSStick to Twin Famicom pin connector (the add on option when ordering)
2) Get a proto board and wire up 2 female 12 pin header connectors and wire them both together pin-to-pin
3) On a blank space for the proto board solder in a male 12 pin connector (the one that goes into port D)
4) Connect the ground and power pins from the 12 pin male into the two 12 pin female adapters (Pins 9 and 10 on Port D, pins 2 and 4 on the RAM adapter cable)
5) Plug in the cable from step one into one of the 2 female 12 pin connectors, connect the stock plug you unplugged and plug that into the other connector
6) Turn on the famicom and you are good to go using the FDSStick GUI, and not having to open the console.


His PCB ends up with 3 connectors 2 female and 1 male. Lets call them F1,F2 and M.
F1 and F2 are directly connected. M shares the ground and vcc pins with F1 and F2.
He then connects what I expect to be the FDSStick to F1, and connect the stock jumper cable in F2.
At that point you should have the jumper wire with a male socket of the type that fits in the D port hanging free.
You could plug this cable in the D port which would make sense. But he claims that the M connector is of the type that the D port uses.
In that case... what to do with that extra male socket?
Quote:
3) On a blank space for the proto board solder in a male 12 pin connector (the one that goes into port D)


Secondly, I don't understand how he counts his pins for the connections between the Female and Male sockets. When I compare it to the stock jumper cable then it just doesn't make sense.
I tried looking for pinouts but I can't find anything. There is a similar pinout of the drive connector inside the twin famicom but it might have a different layout.
Quote:
4) Connect the ground and power pins from the 12 pin male into the two 12 pin female adapters (Pins 9 and 10 on Port D, pins 2 and 4 on the RAM adapter cable)


It would make more sense to me if the male connector was of the port C kind. In that case you would have the jumper connect F1 and D port and the FDSStick to F2 making a direct connection between the drive and the stick. And the male connector which would plug directly into Port C would connect the ground and vcc of the internal ram adaptor to the setup.

Again... any help is really appreciated.
Re: FDSSTICK on twin famicom
by on (#213543)
Hi, for pictures of the C & D connectors and their pin numbers, you can see my post here:

viewtopic.php?f=9&t=16583&p=206032

And this entire thread (though pertinent info is on pages 15-17) is most useful for making your own adaptor/cable to connect the FDSStick to the Twin Fami both for Drive and RAM adaptor emulation.

viewtopic.php?f=9&t=12163&p=164958
Re: FDSSTICK on twin famicom
by on (#213551)
DrWho198 wrote:
I found this post:
viewtopic.php?f=9&t=12163&p=179901&hilit=tototek#p179901

Apparently KittyFae managed to connect the FDSStick in a fully working order. But his explanation is a bit puzzling to me:

Yeah, that was really tough to follow.

If you already have a cable for using fdsstick through port C,
- Make a F2F adapter to join it to port D via the TwinFami's jumper cable.
- Join pins 9,10 (GND,5V) to pins 9,10 on port C.

That's it. (Also remember the famicom needs to be turned on)

Oh, and this looks interesting... https://page.auctions.yahoo.co.jp/jp/auction/w212616256

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Re: FDSSTICK on twin famicom
by on (#213554)
Thanks for all the help.
That makes a lot more sense.

Sadly I could not find the famicom adaptor on tototek. So I'll need to make my own.
The only problem is the plug on the ram adaptor cable. I have no idea where to get a socket for it, but I might do it differently and just add a plug to plug in the FDSStick directly.

Does anyone know what the offset between the fingers is o the FDSStick?
Re: FDSSTICK on twin famicom
by on (#213555)
DrWho198 wrote:
Does anyone know what the offset between the fingers is o the FDSStick?

2.5mm
Re: FDSSTICK on twin famicom
by on (#213566)
It seems like they connected all wires identical to the stock jumper cable, and just soldered the FDSStick lines to it.
I wonder if they would have communication errors when doing this.

Using google translate there is a lot more information to be read. According to the seller there are different models of tf (twin famicom) and the usage of the cable depends on the type of tf.
He also says the way you connect it depends on what you wish to do. My guess is that the different versions he is talking about might be the write protection methods that have been used. The 3 ways are probably;
- plug in D for reading, writing disks
- plug in C for playing FDS files
- plug in C & D without a FDSStick connected for using the twin famicom as a normal twin famicom.

The warning of writing disks is the same for a normal FC + FDS setup. Adding to that the risk that you write while having the cable plugged in wrong would result in data errors.
What is interesting though would be that if this info is right then you could unplug the C port and still use the FDSStick to read/write disks.

Well, that's my guess anyway.

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