Null Terminator

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Quzar
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Null Terminator

Post by Quzar »

Few weeks ago I was finally able to take good pics of one. Cropped them, and here ya'll go. Never seen pics of a Null Terminator online before, so it's a first.
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Null Terminator With Casing.JPG
Null Terminator With Casing.JPG (433.86 KiB) Viewed 2104 times
Null Terminator Outside.JPG
Null Terminator Outside.JPG (337.88 KiB) Viewed 2098 times
Null Terminator Inside 2.JPG
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Re: Null Terminator

Post by emptythought »

where'd you get this?
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Re: Null Terminator

Post by Quzar »

When I ordered a bulk lot of broken DCs ages ago, I got a few of them. AFAIK they were bundled with DCs in Asia, where modems were not included.
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Re: Null Terminator

Post by emptythought »

can i have one :P?
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Re: Null Terminator

Post by |darc| »

What exactly does this do?
It's thinking...
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Re: Null Terminator

Post by emptythought »

Nothing! It's like unplugging a modem and leaving it out but it has the same "functions" as a modem\BBA just with nothing in them.

E.G.

Code: Select all

void DoSomething()
{
    // Don't do anything
}
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Re: Null Terminator

Post by Quzar »

Yea, afaik it does nothing but properly gound some stuff. I did some extensive probing a week or two back trying to figure out the DriKara, and with this plugged in you get different values from reading into unassigned G2 space. (pretty much bit flipped values).
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Re: Null Terminator

Post by |darc| »

That's what I figured, but since the DC works fine without the modem plugged in, I didn't see why there would have been electronic components in a dummy adapter for it.
It's thinking...
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Re: Null Terminator

Post by Quzar »

|darc| wrote:That's what I figured, but since the DC works fine without the modem plugged in, I didn't see why there would have been electronic components in a dummy adapter for it.
And yet, there it is ;). My best theory is that it's 'better' for the DC in some way. Maybe with no device there is active searching for it, while with this, the DC recognizes that there is a null device and ignores it? Or maybe this allows DC software to recognize that it is in a region where the modem is not bundled and act appropriately?
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Re: Null Terminator

Post by Sir Savant »

If you have any other information you've grepped on it, I'd appreciate it. I have some free time this week and should be working on Devcast, so this is an interesting find, to say the least.
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Re: Null Terminator

Post by Quzar »

Well, the only thing I know for sure is what is ind those pictures. These came from what was supposedly a console repair shop and I havn't heard of any others out there. It is only my best guess that they came from (non-Japanese) Asian Dreamcasts, as I have read in multiple places that those did not include modems for some reason or another (cost I think). If that is the case, they would have been there probably to provide a 'base state' for the connector, as it would seem that if they just wanted to protect it or cover it, not actual PCB would be required.

My only other guess is that they could be some sort of repair related item which in conjunction with software could do something like determine if the G2 bus if functioning correctly.

It is very interesting though, as it is one of a very small number of devices that connect to the G2 port.

Oh, btw, Null Terminator is just a name I gave it, as there is no indication that it is called that in any official capacity :P
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Re: Null Terminator

Post by Ex-Cyber »

Quzar wrote:
|darc| wrote:That's what I figured, but since the DC works fine without the modem plugged in, I didn't see why there would have been electronic components in a dummy adapter for it.
And yet, there it is ;). My best theory is that it's 'better' for the DC in some way. Maybe with no device there is active searching for it, while with this, the DC recognizes that there is a null device and ignores it? Or maybe this allows DC software to recognize that it is in a region where the modem is not bundled and act appropriately?
IIRC, the expansion connector is not the only thing connected to that bus. Most likely, the terminator is there because they couldn't guarantee that the bus would "behave" without anything plugged in, and the fact that the system does work is just sort of a happy accident.
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Re: Null Terminator

Post by Quzar »

Ex-Cyber wrote:
Quzar wrote:
|darc| wrote:That's what I figured, but since the DC works fine without the modem plugged in, I didn't see why there would have been electronic components in a dummy adapter for it.
And yet, there it is ;). My best theory is that it's 'better' for the DC in some way. Maybe with no device there is active searching for it, while with this, the DC recognizes that there is a null device and ignores it? Or maybe this allows DC software to recognize that it is in a region where the modem is not bundled and act appropriately?
IIRC, the expansion connector is not the only thing connected to that bus. Most likely, the terminator is there because they couldn't guarantee that the bus would "behave" without anything plugged in, and the fact that the system does work is just sort of a happy accident.
Yea, I've said as much other places, but it's still just conjecture as I can't even be sure where they came from or how they were used.
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