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John Abshier
10-09-2006, 10:18 PM
The picture of the Hydra shows a network connector. Could we have a brief description of this function?

Thanks.

Ken Gracey
10-10-2006, 01:21 AM
John,

Until Andre' replies, I'll provide an answer. It allows two (or more - I forget) Hydra Game PCBs to be connected for multi-player games. It's not an ethernet port for 10/100 Base-T connections.

Ken Gracey
Parallax, Inc.

Paul Baker
10-10-2006, 02:54 AM
Its a twisted pair RJ-11 line capable of full duplex 1.5Mbps communications upto 100' (I think). Short runs have been tested as fast as 2.56Mbps and 100 meters can be operated at 256kbps

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Paul Baker (mailto:pbaker@parallax.com)
Propeller Applications Engineer
[/url][url=http://www.parallax.com] (http://www.parallax.com)
Parallax, Inc. (http://www.parallax.com)

Phil Pilgrim (PhiPi)
10-10-2006, 06:58 AM
Paul,

Any idea where to obtain RJ-11 twisted-pair cable in bulk form (i.e. non-terminated)? All I've ever seen is the flat stuff with conductors running in parallel.

Thanks,
Phil

Paul Baker
10-10-2006, 07:59 AM
Hmmm, maybe I have the twisted pair bit wrong. I know you can use CAT5 with an RJ-11, though that would be wasting half of the wires, PoN (Power over Network) for the unlit wires maybe?

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Paul Baker (mailto:pbaker@parallax.com)
Propeller Applications Engineer
[/url][url=http://www.parallax.com] (http://www.parallax.com)
Parallax, Inc. (http://www.parallax.com)

Post Edited (Paul Baker (Parallax)) : 10/10/2006 1:07:38 AM GMT

Phil Pilgrim (PhiPi)
10-10-2006, 09:14 AM
Paul,

I doubt you have it wrong. I don't think one could get those speeds over plain ol' flat phone cable. But I could be wrong about that.

Do you know what kind of transceiver chips are being used?

-Phil

Paul Baker
10-10-2006, 10:23 AM
I seem to remember from the training (his demo was right before yours if I remember correctly), its a standard phone line. He also makes reference to the cheap and wide availability of the cable in his book (I have read it and it is a good source of information). I could be wrong but I think he just uses a termination resistor, I dont think any tranceivers were used.

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Paul Baker (mailto:pbaker@parallax.com)
Propeller Applications Engineer
[/url][url=http://www.parallax.com] (http://www.parallax.com)
Parallax, Inc. (http://www.parallax.com)

AndreL
10-18-2006, 11:22 AM
The network uses simple 4-conductor phone line from rj-11 to rj-11 jacks. The only thing that is important is the phone line has all 4 conductors (not 2) and that they are reversed or crossed over. Then as mentioned 100 meters at 1.5mb easy full duplex. Plus, there is some added noise cancellation on there via a switch that reduced reflections for really long runs and high speed. So basically, its just a phone line from the store and you are networking!



Andre'