Russell,

It never ceases to amaze me how quickly you research these things... I =20
need to learn your google skills.  I'd go look for a tutorial, but =20
that really is my problem there, isn't it :)

 From your patent reference, I found =20
http://www.eff.org/files/filenode/Lexmark_v_Static_Control/antitrust_compla=
int.pdf now, and a quick skim led me to patent 5398326.  Looks like I have =
a weekend of reading ahead of =20
me.

FWIW, IIRC a patent was valid for 17 years, and recently has been =20
changed to 20 years.  I need to verify that, but if so, I should be =20
good.  I'll report back after some reading.

Thanks,
-Neil.




Quoting RussellMc <apptechnz@gmail.com>:

> 1993 patent appears to be 5210846
>
>
> Here's a 1998 discussion on Dallas 1 wire appolication. Refence 1
> cites a 1997 paper. That's 13 years - about at the upper limit of any
> patent that may have applied originally.
>
>       http://archives.sensorsmag.com/articles/0698/wir0698/index.htm
>
> Half duplex on a single pair was used since time immemorial and hald
> duplex with ground return was used by Noah in the ark ((had problems
> due to poor ground).
>
> Atmel think they/you can do it
>
>          http://www.atmel.com/dyn/resources/prod_documents/AVR274.pdf
>
> 2000
>
>    =20
> http://www.sensorsmag.com/sensors/humidity-moisture/a-1-wire-humidity-sen=
sor-1080
>
> 1997
>
>        Feb. 1997. "Transmitting Data and Power over a One-Wire Bus,"
> Sensors, Vol. 14, No. 2:48-51.
>
> Text from 1997 paper here
>
>                =20
> http://www.datasheetarchive.com/datasheet-pdf/03/DSA0036838.html
>
> Related
>
>              =20
> http://blog.onlinecomponents.com/post/buddy-can-you-spare-an-i-o-pin-try-=
a-1-wire-interface
>
> Patent litigation 1998, re 1993 patent
>
>  http://www.uspto.gov/web/offices/com/sol/og/1998/week30/patrequ.htm
>
>
>
>
>
>
>
>
>
>
>
>
>
>
> On 24 September 2010 01:57, PICdude <picdude3@narwani.org> wrote:
>> Sometime years ago, I had heard (IIRC on this forum) that 1-wire
>> technology is patented, such that I can't implement my own slaves.
>> I've not come up with the patent yet, and Maxim hasn't responded to me
>> yet. =A0Anyone know if this is true, if the patent is still valid, and
>> what the general details are?
>>
>> I want to bi-directional communication to a PIC application, and have
>> only 1 wire available. =A0I also have no room for additional (1-wire
>> slave) chips, but that would be pointless anyway as that slave chip
>> would need more than one wire for communicating with the PIC.
>>
>> If this is not doable, I may end up rolling my own protocol that can
>> work with a single wire, but I'd need to know what specifically is
>> patented with respect to 1-Wire technology.
>>
>> Cheers,
>> -Neil.
>>
>>
>> --
>> http://www.piclist.com PIC/SX FAQ & list archive
>> View/change your membership options at
>> http://mailman.mit.edu/mailman/listinfo/piclist
>>
>
> --
> http://www.piclist.com PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist
>




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