Question about ".xn" file

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mio
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Question about ".xn" file

Post by mio »

I think that information on the writing of ". xn" file is a little.
How I may use it and written?

Some doubts of me were canceled by the following articles.
http://www.xmoslinkers.org/forum/viewto ... ?f=6&t=576
However, it is not complete.


mio / a.k.a. yu-pi-te-ru at http://moxi.jp/
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leon_heller
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Post by leon_heller »

They are written in XML. XML files can be created by the XDE.

Leon
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mio
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Post by mio »

leon_heller wrote:They are written in XML. XML files can be created by the XDE.

Leon
Thanks, Leon.
It wasn't good that I didn't write a question concretely.

For example, It is the following that I want to know.

Code: Select all

  <Links>
    <Link Encoding="2wire" Delays="4,4">
      <LinkEndpoint NodeId="0" Link="1"/>
      <LinkEndpoint NodeId="1" Link="0"/>
    </Link>
  </Links>
This code is from http://www.xmoslinkers.org/forum/viewto ... ?f=6&t=576

What "Delays" attribute means?
How should I decide the number of this "4".
What is it based on?

etc......
mio / a.k.a. yu-pi-te-ru at http://moxi.jp/
Heater
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Post by Heater »

Have a look in the XS1-L System Specification documents. There is a section on the link protocols and switching that will gives some clues.

For example I'm sure "<Link Encoding="2wire" Delays="4,4"> is setting up a 2 wire (in each direction) serial link with 4 clocks delay between data bits and 4 clocks delay between tokens.

Still, where is the xn file actually documented?
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mio
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Post by mio »

Thanks, Heater
Heater wrote:Have a look in the XS1-L System Specification documents. There is a section on the link protocols and switching that will gives some clues.

For example I'm sure "<Link Encoding="2wire" Delays="4,4"> is setting up a 2 wire (in each direction) serial link with 4 clocks delay between data bits and 4 clocks delay between tokens.
If I change "4 clocks delay" to "2 clock delay", what's happen?
This change is OK or WRONG?
If 2 clock is allowed,then this change makes speed it up or down , why etc.....?
I should try each question and report? ;)
Still, where is the xn file actually documented?
Yes, a problem is that the latest document isn't probably introduced to the public. :mrgreen:
mio / a.k.a. yu-pi-te-ru at http://moxi.jp/
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trousers
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Post by trousers »

The full XN specification is in the works. It's not secret; it's just not ready yet.

The "Delays" attribute relates to the number of clock cycles between symbols and the number of clock cycles between tokens. The inter-delay (the second value) must be equal to or greater than the intra-delay (the first value). Additionally, the inter-delay cannot be 0.

Lower numbers will result in data being transmitted more quickly because the link hardware will wait fewer clock cycles between transitions. However, unless your wires are short and noise-free (e.g. on a good PCB) then you will get link errors if you try to go too fast.

The smallest value you can use is "0,1". This is what we use on the XMP board and we've seen no errors there.

When plugging XDKs together with long wiggly cables, "4,4" seems to be reliable whereas "0,1" isn't. When I wan't to be super-sure I use "15,15" (the slowest a G4 can go).

For your own hardware, you need to experiment to find the fastest speed that (a) works, and (b) you're comfortable with. "4,4" is a good starting point in most cases.
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mio
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Post by mio »

Thanks , Awesome_pants
Awesome_pants wrote: The full XN specification is in the works. It's not secret; it's just not ready yet.

The "Delays" attribute relates to the number of clock cycles between symbols and the number of clock cycles between tokens. The inter-delay (the second value) must be equal to or greater than the intra-delay (the first value). Additionally, the inter-delay cannot be 0.

Lower numbers will result in data being transmitted more quickly because the link hardware will wait fewer clock cycles between transitions. However, unless your wires are short and noise-free (e.g. on a good PCB) then you will get link errors if you try to go too fast.

The smallest value you can use is "0,1". This is what we use on the XMP board and we've seen no errors there.

When plugging XDKs together with long wiggly cables, "4,4" seems to be reliable whereas "0,1" isn't. When I wan't to be super-sure I use "15,15" (the slowest a G4 can go).

For your own hardware, you need to experiment to find the fastest speed that (a) works, and (b) you're comfortable with. "4,4" is a good starting point in most cases.

It found out the thing which I wanted to know now. :D

I am looking forward to the completion of the full XN specification.
mio / a.k.a. yu-pi-te-ru at http://moxi.jp/
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AtomSoft
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Post by AtomSoft »

Wow i thought i was the only one who was like where is the info heh...

mio thanks for that link!
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