Class 2 serial data components
Thread Starter
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Joined: Apr 2008
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From: Paris
Class 2 serial data components
Hi,
After going through the GM Manual, I'm under the impression that the class 2 serial data components are in fact set up in parallel.
Is this a fair statement?
a++ Cedric
After going through the GM Manual, I'm under the impression that the class 2 serial data components are in fact set up in parallel.
Is this a fair statement?
a++ Cedric
Safety Car
Joined: Nov 2006
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From: San Jose California
Actually, the class 2 bus (a serial bus, not parallel) is set up in a classic star configuration.
Here's a good read on this topic:
http://www.pdfone.com/download/23_ke...ms-a-short.pdf
Z//
Here's a good read on this topic:
http://www.pdfone.com/download/23_ke...ms-a-short.pdf
Z//
Thread Starter
Pro
Joined: Apr 2008
Posts: 728
Likes: 30
From: Paris
Actually, the class 2 bus (a serial bus, not parallel) is set up in a classic star configuration.
Here's a good read on this topic:
http://www.pdfone.com/download/23_ke...ms-a-short.pdf
Z//
Here's a good read on this topic:
http://www.pdfone.com/download/23_ke...ms-a-short.pdf
Z//
Le Mans Master
Joined: Dec 2004
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From: West coast CA
I'm not sure what's being stated. GM's "Class 2" is their version of SAE J1850, which is a serial digital interface. Data comes down the wire a bit at a time.
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Joined: Apr 2008
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From: Paris
I understand that it is serial bus, my question is how the components are connected to this bus.
You can have a serial communication bus were the components are daisy chained - or mounted serially (in which case the failure of a component will disconnect other components from the bus).
You can have a serial communication bus where components are mounted in parallel (or star configuration, which ever denomination makes you happy), in which caase the failure of one component will not affect others.
My understanding is that the components in the Class 1 serial bus (requiring real-time connectivity) are mounted in a serial manner (daisy chained) whereas those in the class 2 serial bus are in a star/parallel connection.
For example, those who desired to remove the OnStar module had to connect the in link with out link in order to ensure functionality of the class 1 bus where as the SLCM can just be removed from the bus, other components will continue to function.
a++ Cedric
Safety Car
Joined: Nov 2006
Posts: 4,023
Likes: 266
From: San Jose California
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