ultraturtle0
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Hello all!

I've been trying to get my LSDJ Keyboard to work, as I'm doing something a little unconventional... I'm mounting 4 female PS/2 jacks in a DMG-07, and wiring them where the individual link ports are mounted on the board. To test this, I wired a jack to the board right where the built-in cable connects. When I plug the cable in, my Gameboy instantly crashes. I had it wired incorrectly before, and it recognized the keyboard, but didn't receive input, and made LSDJ glitchy. Now I'm just getting a hard crash - screen goes blank, but backlight is still on... Any suggestions? I can post pictures if needed.

Thanks in advance!

Telerophon
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Austin, Texas

I don't think the DMG-07 is compatible with the same protocol as the LSDj sync function.

I'm not an expert on the way four-player sync worked on the earliest Game Boy games, but a DMG-07 isn't just a straight pass-through. That's why people who modify a DMG-07 into a 3x1 Sync Box have to modify them--they don't "just work" with LSDj's sync function.

Anyway, a PS/2 port and the Game Boy link port are both six-pin serial ports: The only thing that is different is the plug interface. So, if you are just changing the plug interface superficially, and not the actual wiring of the DMG-07, I don't think it will work.

The Keyboard sync function in LSDj isn't a normal sync function, either. I can't image it working with any kind of complex circuit interfering with the four lines that have to go from the game boy to the keyboard. That is, unless you built something that simulated keyboard input, perhaps with Arduino, and used that in lieu of a keyboard…

I'm rambling here, but my point is that I don't think a keyboard attached to a DMG-07 attached to a DMG-01 is going to work. At all.

EDIT: If I'm wrong, someone please correct me. I'm definitely not an expert on the DMG-07.

Last edited by Telerophon (Jul 25, 2012 10:17 pm)

ultraturtle0
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I understand it isn't a straight pass-through, which is why I am completely bypassing the DMG-07 circuitry and soldering directly where the jacks meet the board. Long term, I'd like to modify the board to support a 4-way LSDJ link OR four DMG-01s with four separate keyboards. As of right now, I'm just trying to get one keyboard to work; the 07 is just kind of a breadboard. tongue Just wondering if anyone else got hard crashes with their keyboards, and if they found solutions.

Telerophon
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Austin, Texas

I have never gotten a hard crash with my keyboards, but I did managed to freeze LSDj a few times by trying to run a table when I had the tempo set to 255 and the groove set to 1/1.

To be honest, I don't entirely understand what you are trying to do with the DMG-07. hmm

A Game Boy can only handle one serial input. I don't think you'll be able to sync it externally and use a keyboard on the same bus at the same time.

ultraturtle0
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I'm not expecting to, I'm trying to build an all-in-one interface that can either link Gameboys OR offer keyboard connections. Not both on the same 'Boy.

The keyboard should be able to power off of the link port, right? I thought at first that the backlight + keyboard could be too much of a power draw for batteries, but I'm getting the same thing with a wall charger...

Telerophon
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Austin, Texas

A keyboard can easily be powered off of the DMG-01 link port, you just need to make sure that +5V and GND from the keyboard connect to the corresponding points on the link port.

That said, I don't think the three ports on the DMG-07 provide power… I'd have to take my stock one apart to look, but the DMG-07 receives power from the Player 1 Game Boy, and the other three link cables in a four player setup don't carry power. I wouldn't think the  P234 ports are powered.

I'm getting confused by what you are describing here:

ultraturtle0 wrote:

Long term, I'd like to modify the board to support a 4-way LSDJ link OR four DMG-01s with four separate keyboards.

This, to me, sounds like you are trying to sync four Game Boys while providing them all with individual keyboard inputs.

To my knowledge, this is impossible; the link port bus can only support one function, even if you did have another port soldered on somewhere.

For example, people who add PS/2 ports to their DMGs: You can have a keyboard and a link cable plugged in at the same time, but you can only use one interface at a time.

ultraturtle0
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ultraturtle0 wrote:

OR

As of right now, I am testing one Gameboy (essentially) connected to a keyboard. In the future, each Gameboy will have the option of being linked to another Gameboy, OR powering it's own independent keyboard. Again, I am not doing both at the same time; it's outside the scope of LSDJ.

Right now, I am just trying to solve a crash problem. I haven't found any mods online that wire a link cable port and a female PS/2 port together, so I have no real frame of reference. All of the available tutorials involve cutting apart a powered link cable and a computer keyboard cable, which is what I'm trying to avoid by having a versatile, modular enclosure.

Telerophon
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Austin, Texas

I've built Male DMG-04 to Female PS/2 adapters, that's worked quite well for me. I think it's the cheapest and lowest material way to hook a keyboard up to LSDj, and you get two of them for the price of one link cable.

The trick is that you have to swap pins in the DMG-04 so that the adapter will carry power to the keyboard,

Here's a picture of what my working adapter looks like on the inside:

I recommend checking the pinouts in the LSDj Wiki's keyboard article, and remember that if you are looking into the female PS/2 port, that +5V should be on the left, and that GND, CLK, and SIN should be on the right. That's where I messed up the first time.

I hope that helps.

EDIT:

Oh, you meant "I haven't found any mods online that wire a link cable port and a female PS/2 port together" as in the two ports being in a device, not an adapter from one to the other.

Well, that is essentially how installing a PS/2 port in a DMG-01 works. I just don't think it'll work in a DMG-07.

Last edited by Telerophon (Jul 26, 2012 12:44 am)