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Re: Micro controllers with UHF transceivers?
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Hmm, did they really say "not for volume production"? That thread was
half a year ago and they still offer the chips. Also, I wonder what
alternatives there really are if 2.45GHz ain't cutting it because of
lack of range.

Maybe I should resort to rolling my own, just like I usually do in the
analog world.

--
Regards, Joerg

http://www.analogconsultants.com /

Re: Micro controllers with UHF transceivers?
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I don't suppose you came across any receive-only chips (rx + microcontroller)
in your search, did you?

Presumably there's nothing wrong with using one of those ChipCom ICs in
receive-only mode, although the currents are a little higher (18.9mA) than I'd
like and I'm thinking that perhaps an IC optimized as receive-only could be
less.

Thanks,
---Joel



Re: Micro controllers with UHF transceivers?
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Actually yes but I tossed them all because long term they aren't useful
for me. There has to be feedback about machine status.


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The only disconcerting thing is that Digikey doesn't seem to carry them.
Usually a red flag for me, so Lewin might have a point here. But what
alternatives are there really? Maybe we should stay with the two-chip
strategy for a while until the dust has settled.

--
Regards, Joerg

http://www.analogconsultants.com /

Re: Micro controllers with UHF transceivers?

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I think that the MSP430 with on-chip RF is going to replace the 51
parts.

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Sure, but the target markets for much of Chipcon's stuff would benefit
from an MSP430 core.

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Depends on the application. In my day job I work a little lower down
in the band, ASK, low duty cycle.

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Eh? Did you find your way to this page: <http://www.atmel.com/dyn/
products/devices.asp?family_id65%1>


Re: Micro controllers with UHF transceivers?

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Oh, wait a moment, never mind :)


Re: Micro controllers with UHF transceivers?
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But when? Waiting since over a year now ...

Thing is, my clients need designs now, not next year.


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If it comes to market.


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Says "Directory Listing Denied" :-(

--
Regards, Joerg

http://www.analogconsultants.com /

Re: Micro controllers with UHF transceivers?
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The URL was broken, need to re-join it:
<http://www.atmel.com/dyn/products/devices.asp?family_id65%1>.

Is there anything with receive that reaches down to 144MHz (2 meter)
band?

Re: Micro controllers with UHF transceivers?
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Thanks. But same as usual, only TX with uC, not transceivers with uC.


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You'll have to study the data sheets in detail, see if it can be goosed
down via another master oscillator etc. Most likely not if there are
frequency dependent parts inside. The area below 300MHz seems to be
strictly discrete and ASIC territory.

--
Regards, Joerg

http://www.analogconsultants.com /

Re: Micro controllers with UHF transceivers?

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If it's any consolation, I think the market will be saturated with
these devices in 18 months. There is some new European boondoggle
going on (at least this one will make money, unlike RoHS). I didn't
pay much attention but it is something to do with energy efficiency/
heating.


Re: Micro controllers with UHF transceivers?
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I wouldn't count too much on such political efforts. We had that here in
CA at times, the governor even visited Echelon. But the stuff is so
expensive that most everyone stays with the true and tried. Or even goes
backwards to older technology to wiggle out of the fossil fuel rat race.
Like us when we installed wood stoves.

My faith in electronic controls of heating equipment has sagged after
every repair. My favorite gear is the living room wood stove. Except for
the blower speed control (which can be disabled) the number of
electronics parts is zilch.

--
Regards, Joerg

http://www.analogconsultants.com /

Re: Micro controllers with UHF transceivers?
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only found one uC family that has serious
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brethren. rfPICs and others usually only have a
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for range reasons. Is anything coming down the
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datasheets today. Five bucks is a bit highish
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I suggest that. It's a 8051 core (I love the
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That's a neat part. 2 wire programming too.

Cheers



Re: Micro controllers with UHF transceivers?
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Mmm... have you ever tried an AVR or an MSP430?

Of course, if they're programming in C it's a relatively moot point -- the
move to using higher-level languages has, IMHO, keep a lot of
less-than-stellar CPU architectures viable.  (Not points for lumping x86 into
that list :-) ).

---Joel



Re: Micro controllers with UHF transceivers?
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Yes, the MSP430 but they are still too expensive.


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For most of my clients this is the order of priority:

1. Cost
2. 2nd Source
3. 2nd Source
4. 2nd Source

--
Regards, Joerg

http://www.analogconsultants.com /

Re: Micro controllers with UHF transceivers?

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Atmel:
<http://www.atmel.com/dyn/products/devices.asp?family_id65%1>

--
Jeff Liebermann     snipped-for-privacy@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
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Re: Micro controllers with UHF transceivers?
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The ATA chips don't contain a micro controller ;-)

--
Regards, Joerg

http://www.analogconsultants.com /

Re: Micro controllers with UHF transceivers?

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Oops.  Only the transmitter is integrated with a MARC4 controller on
the ATAR862-8.  The receiver is stand alone.   Sorry.

--
Jeff Liebermann     snipped-for-privacy@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
We've slightly trimmed the long signature. Click to see the full one.
Re: Micro controllers with UHF transceivers?

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If it is a 2.4GHz transceiver you need (and not a complete wireless USB
link), you should have a look at www.nordicsemi.com. If you can live
with a 8051-compatible CPU core (_you_ can, I suppose), something
like the 24E1 might be a reasonable choice.

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What range do you need? With chips from Nordic, we ended our free air
tests when the parking lot of the company ended - nearly 100m, and zero
transmission errors. Ok, in a crowded train station it was about 30m
with 50% errors.

Regards
Michael

Re: Micro controllers with UHF transceivers?
On Wed, 24 Oct 2007 13:34:29 -0700, Joerg

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It would help if you had specified the country in which it should
operate. The frequency bands, the power levels and duty cycles vary
with country or at least with continent.

You said that the range was too short on 2.45 GHz. What kind of
propagation environment do you have ? Free space, lot of thick trees,
indoor or what ?

In a free space environment, the capture area of an omnidirectional
receiver antenna at a higher frequency can get quite small, thus the
receiver signal will be weaker. Also a lot of wet trees will attenuate
the 2.45 GHz signal.

On the other hand, in typical indoor situations and at the streets of
a large city, there are going to be plenty of reflections and the
propagation is more or less independent of the frequency. The shorter
wavelength might even propagate more easily through narrow slits in
air conditioning ducts etc.

Paul


Re: Micro controllers with UHF transceivers?
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As many countries as possible. Definitely US, Canada, Europe and in and
around the Gulf of Mexico, other cases also Asia. That leaves 433MHz and
2.45GHz. Or frequencies below 100MHz but there aren't any integrated
solutions for those.


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All of the above, usually comms between a pod inside the house to
equipment outside. I guess our house would be the worst case, woodframe
construction with aluminum backed insulation inside the walls.


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All I can say that around our house 2.45GHz does not work reliably at
all. <200MHz works excellent.

--
Regards, Joerg

http://www.analogconsultants.com /

Re: Micro controllers with UHF transceivers?
On Thu, 25 Oct 2007 12:54:07 -0700, Joerg

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At least in Europe, the available bands would be 2.45 GHz, 433 MHz, 27
MHz and 13.56 MHz. Please note that in Europe, you might encounter
1-100 W amateur radio transmissions at the same or very close
frequencies in the 433 MHz and 2.45 MHz band, so a good front end
selectivity would be required. On 27 MHz 5 W CB transmissions could
occur close to your frequencies and especially during the sunspot
maximum, the HF frequencies may have strong signals from sources
1000-2000 km away. Also the 13.56 MHz band may have strong RFID
signals.

While the omnidirectional receiver antenna capture area is small on
2.45 GHz, this is not a problem on HF/VHF frequencies, in which a
miniature receiver antenna is capable of receiving the band noise, but
at to lower frequencies, the problem is the transmitter antenna
efficiency. When the antenna dimension goes below about 1/10
wavelength, the radiation resistance drops quite low and the
transmitter antenna efficiency is quite low.


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Unless your windows are coated with some heat reflecting film, the UHF
signal should easily pass through the windows.

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If there is a wood outside your window (no reflecting houses on the
other side of the street), you might not get much signal from a pod
just below your window to a receiver inside your house.

When using the license free frequency bands with legal power levels,
one should expect 10-100 m reliable communication in typical
conditions.

While the system might work in some extraordinary situations for
several kilometers (and this is used by the marketing droids) the
typical distance is much less and the worst case situation might be
less than 1 m. For instance the car key systems operating at 433 MHz
might not work even if the key is just outside the windscreen, if
there is a strong amateur radio transmission nearby somewhere in the
432-434 MHz range.

Paul
 

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