Does anyone know

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Bufferstop
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Does anyone know

Postby Bufferstop » Wed Mar 09, 2016 1:05 pm

I asked this question on another thread but it really should be on here so I'll ask it again. That the facility to run a non equipped loco is at address 0 makes some sort of sense, but why is the default address 3. My guess is that it has something to do with 011 binary being the result of two switches, physical or virtual being set to on. In the days when DCC was being thought out addressing on many devices was done by physically moving switches in a minute block of 8 and two out of the eight wouldn't be too hard for the assembly slaves to get right.
My odd mental processes would like to hear others thoughts, or perhaps someone has even found out.
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castlespitfire
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Re: Does anyone know

Postby castlespitfire » Wed Mar 09, 2016 1:15 pm

Dont know but thought it would be nice for you to get a reply :lol:
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alex3410
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Re: Does anyone know

Postby alex3410 » Wed Mar 09, 2016 2:03 pm

never really thought about it but would be interesting to know - probably someone rolled a dice or something :lol:

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RAF96
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Re: Does anyone know

Postby RAF96 » Wed Mar 09, 2016 3:08 pm

I have a book written by an NMRA guy and they set the rules so I'll have a snout through it again and get back if there is any good reason for the 03 default.

Edit:
Read it front to back and been on the inter web looking at NMRA specs and reccomended practices, but although 3 is well known as the default address, it's is not an NMRA mandate although most manufacturers seem to have adopted it.

Sorry to have been no help at all.
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Flashbang
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Re: Does anyone know

Postby Flashbang » Wed Mar 09, 2016 6:45 pm

Some four or more years ago I asked the NMRA as to why was 3 the default address number rather than 1 etc? Having previously asked the same question on a couple of forums and got no sensible answer.
The NMRA did reply saying they didn't know! Not sure if I kept the email now? Will have a look.

So for me it remains a total mystery!
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Bufferstop
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Re: Does anyone know

Postby Bufferstop » Wed Mar 09, 2016 8:11 pm

Thanks for joining in, I'm not the only one who has to scratch the curiosity itch.
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BananaRepublic
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Re: Does anyone know

Postby BananaRepublic » Sun Mar 13, 2016 9:21 am

It's because 3 comes between 4 and 2.
Which is symbolic as the answer to the ultimate question of life, the universe and everything is 42.




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PinkNosedPenguin
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Re: Does anyone know

Postby PinkNosedPenguin » Sun Mar 13, 2016 9:24 am

BananaRepublic wrote:It's because 3 comes between 4 and 2.
Which is symbolic as the answer to the ultimate question of life, the universe and everything is 42.

:lol: Excellent answer! (and I suspect the most plausible anyone can come up with!)

GaryAM
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Re: Does anyone know

Postby GaryAM » Sun Mar 13, 2016 3:05 pm

perhaps they are 'spares' for future development?

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Bufferstop
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Re: Does anyone know

Postby Bufferstop » Sun Mar 13, 2016 5:09 pm

42 :D
If 1 and 2 were reserved for some future use it would be in the documentation somewhere, in the hope that manufacturers wouldn't use them for a conflicting purpose.
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michaelasc
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Re: Does anyone know

Postby michaelasc » Sun Mar 13, 2016 7:40 pm

They say the best things in life comes in threes. There were three blind mice after all and don't get me started on the french hens.

All of which means I have absolutely no idea other than I like to reply to threads which are fun
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alex3410
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Re: Does anyone know

Postby alex3410 » Mon Mar 14, 2016 8:44 am

maybe it has something to do with 'testing' the chips in the factory?

Bigmet
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Re: Does anyone know

Postby Bigmet » Mon Mar 14, 2016 8:50 am

The original developer thought in terms of two locos able to run on the same track. So the owner will naturally take addresses no 1 and no 2 for those, so we will make the factory setting no 3. Me joko!

I suspect Bufferstop's thought of the two lowest value dip switches being on for binary 11 is likely correct.

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Bufferstop
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Re: Does anyone know

Postby Bufferstop » Mon Mar 14, 2016 10:06 am

That's equally plausible Bigmet, Can't get you with this binary joke
There are 10 people who understand binary, you must be the other one.
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Forfarian
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Re: Does anyone know

Postby Forfarian » Mon Mar 14, 2016 10:48 am

Its the low temperature they cook the chips at!
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