PIC to USB to 802.11g to USB to PC ?

"bit eimer" <bit_eimer.keinewurst@ten.xoc> wrote:

>Hi all,
>
>I'm usually just a lurker.  But now I'm getting interested in doing a link 
>from an 'F877 to a PC:
>
>PIC s/w -> UART -> USB (adapter) -> 802.11g (adapter)  --//--> 802.11g 
>(adapter) -> USB -> Win XP -> app s/w

Sounds unnecessarily complex, why not just connect an 802.11b PCMCIA
or CF card directly to the PICmicro? It might be a bit tricky because
of the small amount of RAM on the PIC16F877, but a PIC18F452 works
just fine.

>Have chosen neither the USB adapter nor the 802.11g adapter yet.  And I'm 
>fairly concerned about the potential complexity of USB and 802.11g protocols 
>that I will have to implement on the PIC side.

You don't have to understand the inner workings of 802.11, as the WLAN
card processor does all the hard work; once set up, it provides a raw
data link similar to Ethernet. You can invent your own communication
protocol to run over this link, but most people use TCP/IP. If you're
a newcomer to this protocol family I'd suggest checking out UDP,
because it is realtively easy to implement and debug.

>Any one have advice on any part of the above or pointers to some actual 
>implementations I could possibly leverage or adapt?

 www.iosoft.co.uk

>BTW, I'm leaning toward 802.11g rather than Bluetooth in order to achieve 
>higher (I think) outdoor range.  Any confirmation of that assumption?

I don't know much about Bluetooth, but the usual quoted range seems to
be 10 meters (32 feet) as opposed to 100 meters or more for 802.11 -
but of course this depends on the type of antennas, obstructions etc.

Jeremy Bentham
Iosoft Ltd.

"bit eimer" <bit_eimer.keinewurst@ten.xoc> wrote :

> Mea culpa,  my source (the following article) discusses g vs a,
> not g vs b. It appears g and b are about equilvalent on range,
> albeit not on data rate. 
> 
> http://www.commsdesign.com/story/OEG20030114S0008

great, but OFDM works at speeds >= 6Mbit/sec.
Every 802.11G chip falls back to CCK@5.5Mbit/sec DQPSK@2Mbit/sec and 
DBPSK@1Mbit/sec if it cannot establish 6Mbit/sec link. And sensitivity 
at >11Mbit/sec sucks. Those faster speeds are available only if strong 
signal is present. Full 54Mbit (real 34Mbit) speed is only possible in 
the same room :).

Pozdrawiam.
-- 
RusH   //
 http://randki.o2.pl/profil.php?id_r=352019
Like ninjas, true hackers are shrouded in secrecy and mystery.
You may never know -- UNTIL IT'S TOO LATE.

Hi,

indeed, by using modules you don't have to worry about WLAN driver or
TCP stacks.

The company I work for builds modules which connect to WLAN on one side
an RS232 on the other side. By using simple "AT" commands or by
configuring the module over a website you can set up a connection to
another modul, to a PC or to the Internet. Your PIC does not need any
protokoll stuff.

Take a look at www.avisaro.com . Contact me if you need an English
speeking person.

If you are concerned about outdoor range, use 802.11b rather than
802.11g . The rule of thumb is: the higher the bandwith the lower the
range.

Most Bluetooth modules have a range of 10m, only a few provide 100m.
The main difference is the protokoll: if you need network connectivity,
you don't get TCP or UDP with Bluetooth modules (at least the one I
know). If you only need a point to point connection, you are fine with
bluetooth.

Matthias Colsman
Avisaro AG

Hi,

indeed, by using modules you don't have to worry about WLAN driver or
TCP stacks.

The company I work for builds modules which connect to WLAN on one side
an RS232 on the other side. By using simple "AT" commands or by
configuring the module over a website you can set up a connection to
another modul, to a PC or to the Internet. Your PIC does not need any
protokoll stuff.

Take a look at www.avisaro.com . Contact me if you need an English
speeking person.

If you are concerned about outdoor range, use 802.11b rather than
802.11g . The rule of thumb is: the higher the bandwith the lower the
range.

Most Bluetooth modules have a range of 10m, only a few provide 100m.
The main difference is the protokoll: if you need network connectivity,
you don't get TCP or UDP with Bluetooth modules (at least the one I
know). If you only need a point to point connection, you are fine with
bluetooth.

Matthias Colsman

Avisaro AG


Jeremy Bentham wrote:
> "bit eimer" <bit_eimer.keinewurst@ten.xoc> wrote:
>
> >Hi all,
> >
> >I'm usually just a lurker.  But now I'm getting interested in doing
a link
> >from an 'F877 to a PC:
> >
> >PIC s/w -> UART -> USB (adapter) -> 802.11g (adapter)  --//-->
802.11g
> >(adapter) -> USB -> Win XP -> app s/w
>
> Sounds unnecessarily complex, why not just connect an 802.11b PCMCIA
> or CF card directly to the PICmicro? It might be a bit tricky because
> of the small amount of RAM on the PIC16F877, but a PIC18F452 works
> just fine.
>
> >Have chosen neither the USB adapter nor the 802.11g adapter yet.
And I'm
> >fairly concerned about the potential complexity of USB and 802.11g
protocols
> >that I will have to implement on the PIC side.
>
> You don't have to understand the inner workings of 802.11, as the
WLAN
> card processor does all the hard work; once set up, it provides a raw
> data link similar to Ethernet. You can invent your own communication
> protocol to run over this link, but most people use TCP/IP. If you're
> a newcomer to this protocol family I'd suggest checking out UDP,
> because it is realtively easy to implement and debug.
>
> >Any one have advice on any part of the above or pointers to some
actual
> >implementations I could possibly leverage or adapt?
>
>  www.iosoft.co.uk
>
> >BTW, I'm leaning toward 802.11g rather than Bluetooth in order to
achieve
> >higher (I think) outdoor range.  Any confirmation of that
assumption?
>
> I don't know much about Bluetooth, but the usual quoted range seems
to
> be 10 meters (32 feet) as opposed to 100 meters or more for 802.11 -
> but of course this depends on the type of antennas, obstructions etc.
> 
> Jeremy Bentham
> Iosoft Ltd.

Dass sieht interesant aus, aber die Frage ist, uber wieviel Meter kann mann 
diese WLAN benuetzen?  Dass habe ich nicht gefunden auf deine Website.

(Ja, ich weiss, mein Deutsch ist beschissen)

-- 
...The Bit Eimer     NAR 84054      L0
"My goal in life is to be the kind of person my cat thinks he is"
[remove keinewurst and reverse letters in domain to email me]
--------------------------------------------------------------


<matt@avisaro.com> wrote in message 
news:1103193084.878843.10700@c13g2000cwb.googlegroups.com...
> Hi,
>
> indeed, by using modules you don't have to worry about WLAN driver or
> TCP stacks.
>
> The company I work for builds modules which connect to WLAN on one side
> an RS232 on the other side. By using simple "AT" commands or by
> configuring the module over a website you can set up a connection to
> another modul, to a PC or to the Internet. Your PIC does not need any
> protokoll stuff.
>
> Take a look at www.avisaro.com . Contact me if you need an English
> speeking person.
>
> If you are concerned about outdoor range, use 802.11b rather than
> 802.11g . The rule of thumb is: the higher the bandwith the lower the
> range.
>
> Most Bluetooth modules have a range of 10m, only a few provide 100m.
> The main difference is the protokoll: if you need network connectivity,
> you don't get TCP or UDP with Bluetooth modules (at least the one I
> know). If you only need a point to point connection, you are fine with
> bluetooth.
>
> Matthias Colsman
> Avisaro AG
> 

The range of WLAN is typically 300 meter outdoors and 30-50 meter
indoor (through walls and sealings). This holds true for the Avisaro
Moduls as well.

If you have lots of steel and concrete around you, the range is at its
lower end - with wood and open space the range is at its higher end.
Hope that helps.

Matt