Hexadecimal Address - What's in a number?

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DV52

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Yes, I'm aware that some of my questions can be a tad "ephemeral" and some-what esoteric, but this one has me really stumped! So, I once again ask for the patience of the more knowledgeable folk here, as I seek your advice regarding yet another VCDS conundrum!

My question relates to the otherwise seemingly pedestrian issue of control module addressing and I guess that the best way for me to explain my dilemma is by way of an example:

I was recently playing with the settings in the KESSY module on a mk7 and I noticed something really odd about how VCDS reports the control module address. Here's a picture of the Gateway list from my test bench using my trusty HEX-NET cable:



Notice that the hexadecimal address for the KESSY module (i.e Acc/Start Auth.) is hex05.

And here is a picture of the Gateway list from another diagnostic cable, also plugged into my test bench:



Notice that it reports the KESSY module (which is described differently - nothing odd about that) at address hexB7

And just to confirm the "uniqueness" of the VCDS screen here's how yet another diagnostic device (it's actually a dongle), reports the same Gateway listing


Notice that it aligns with my second picture.

All the same screens apply when I hook-up the 3 x diagnostic devices to my "physical" mk7 (as district from my "virtual mk7")

So here's my question: I had thought that the control module address is determined by the car's own network protocols (i.e. module address was not dependent on the make of diagnostic cable/dongle that was plugged into the OBD port). My expectation (incorrect as it now appears) was that any OBD device would read the SAME module address, regardless of its manufacture!

What am I missing?

Don
 
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Uwe

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For the sake of consistency across old and new car platforms, VCDS displays (and sorts) modules by the traditional K-Line addresses.

The physical addressing in CAN based cars can't be expressed in two characters anyway (it's a minimum of 11 bits).

I'm not sure where the B7 comes from for Kessy in those other tools; I'd have to do a bit of digging to find out.

-Uwe-
 
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NEtech

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I'm not sure where the B7 comes from for Kessy in those other tools; I'd have to do a bit of digging to find out.
I have been digging :cool: FS #923 and e-mail Nov.4.2015
 
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DV52

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NEtech: What is "FS #923" and does it contain any information of a non commercial nature that is able to be disclosed? I simply ask for no other reason than the pure pursuit of knowledge

Don
 
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Uwe

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What is "FS #923"
It's a reference to an entry in our bug tracking system, where Niels reported the same thing back on 2015-03-30.

-Uwe-
 
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DV52

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It's a reference to an entry in our bug tracking system, where Niels reported the same thing back on 2015-03-30.

-Uwe-
Arrhhhh.................. a bug? Good - I hope that my revived confidence is not misplaced, but now I don't feel so idiotic (just a tad stupid)!!

NEtech: Thanks, great minds think alike - let's not contemplate the other part of this saying!!

Don

PS: I now remember your "FS" facility from an earlier conversation with Dana. I think we agreed that "FS" was short-hand for "Fantastic Suggestion", but I could be mistaken in my recollection!
 
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