Wireless question?

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My understanding is that you are required to submit to FCC/CE testing for wireless (get a license) unless you use a preapproved module. Is this correct? The modules seem to be I/O pin limited.

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Technically, if you are going to sell it, yes. Though, it won't be a "license", per se, but only verification that the device fits the requirements to operate as an unlicensed device. This includes things like transmitter power level, spurious emissions, and such.

The existing modules are generally designed to be serial links between smarter devices (typically microprocessors). So, those smarter devices are intended to handle the I/O, not the transceiver, itself. Yes, they are pin limited. You don't need many pins for antenna, power (and ground), receive output and transmit input. Even with low power devices, this is not always easy to satisfy.

There is one manufacturer (forget which at the moment) that does make a module that mates with an encoder (such as for connecting push buttons) and a decoder (for activating multiple load devices). I think the encoder/decoder comes from Holtek (spelling ?). This is intended for devices such as key locks, as I recall.

Jim

 

Until Black Lives Matter, we do not have "All Lives Matter"!

 

 

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Even with an approved module, the whole system probably has to conform with the regulations, which requires testing.

Leon

Leon Heller G1HSM

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Quote:

The modules seem to be I/O pin limited.

Well, I guess technically all modules (and chips and the like) are limited, 'cause they ain't >>un<< limited. :twisted:

I guess first mention how many pins you need, and whether you are just doing "remote control" or passing messages. I've used "remote control" simple keypress TX/RX module sets with 8 pins, and also full-featured "packet" modules with 8 GPIO plus sume analog capability.

Lee

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

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In the past we have submitted our products to commercial CE test labs. With Wireless onboard, would we have to obtain a license or just pass the usuall emmission and suseptability test?

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You also have to pass the usual tests for radio systems, and might need licensing as well. It depends on the country into which the equipment is sold. Licensing is administered by Ofcom in the UK.

http://www.ofcom.org.uk/

Leon

Leon Heller G1HSM

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For unlicensed operation, its just emissions and susceptibility. Since it is an intentional radiator, there may be a different emissions mask (for example, there may be special attention to harmonics), but it is basically the same thing, AFIK.

If it also has a micro, the testing will look at all of the emissions stuff that you have probably been though before.

Jim

 

Until Black Lives Matter, we do not have "All Lives Matter"!

 

 

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theusch wrote:
Quote:

The modules seem to be I/O pin limited.

Well, I guess technically all modules (and chips and the like) are limited, 'cause they ain't >>un<< limited. :twisted:

I guess first mention how many pins you need, and whether you are just doing "remote control" or passing messages. I've used "remote control" simple keypress TX/RX module sets with 8 pins, and also full-featured "packet" modules with 8 GPIO plus sume analog capability.

Lee

One of my products has a Mega128, LCD Char display, Keypad, I/O pins for external inputs, relays, spi to DAC and ADC, etc. So when I look at a canned module with maybe 8 pins available I am thinkin I have to roll my own.

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??? How much of all that are you going to expose to the wireless link? I don't get it--you want to wire many/most of your Mega128 pins right to a wireless module and have the state of them appear remotely? You've lost me completely.

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

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theusch wrote:
??? How much of all that are you going to expose to the wireless link? I don't get it--you want to wire many/most of your Mega128 pins right to a wireless module and have the state of them appear remotely? You've lost me completely.

To be clear I am talking about the ZigBit modules shown on Atmel web. One data sheet says it has 9 GPIO pins. It has an ATMEGA on the module but many pins are used already. So my point was I am paying for an AVR and the Wireless chip in the module price. The promo says you avoid the license issue as they have one. So I would have liked to make use of the AVR in the module for all my products needs.

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Oh, I get you now. Another example is the Atmel Raven series, with a '1284 doing the protocol and a separate AVR for the "app" including the LCD.

I guess the defining factor for me might be how extensive my app is, and how extensive (flash size, processor cycles) the protocol is. Otherwise an extensive (read: cycle-sucking) app of mine might interfere with reliable operation of the protocol.

If it were me for production, I'd go for the certified module every time. Even if it meant adding another micro for the app. For a one-off the FCC probably ain't gonna find you, but the roll-your-own cost probably exceeds the extra micro.

In addition, I'll trust the RF engineers and a "good" module as having the proper ground planes and antenna design and the like. So putting my app next to it and staying away form the RF stuff sounds like a safe bet (e.g., see the general layout of the Raven).

[Side note on that: if not overkill/too big, consider the Raven itself as the unites are sold separately and we couldn't build them for the price.]

Lee

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

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Thanks for your comments Lee. I have a Raven kit. I wish the USB stick had an enclosure.

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Basically the FCC requires grant certification (testing) on any device that is an intentional radiator. If you use an intentional radiator that already has part 15 modular approval for license-free operation, then you can use the device in your product without further testing. You may need to do a declaration of conformity. This is basically where you do your own tests and keep records. A device that contains a modular radio must also have a visible label that states something like "this device contains a xxx module, FCC ID, and also states the part 15 interference stuff".

This is just my understanding, so be sure and do your own reading on the subject. I have been through the grant certification process before. There is quite a bit more to that in terms of required documentation and testing. It can be expensive. Expect to pay at least 10k for tests related to a spread spectrum device.

btw, the best way to learn more about the requirements is to find a similar device and go to the FCC's web site and study the testing reports. They are public information.

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Seems like an approved module is the way to meet FCC regulations. The Raven is not for use in a product as it is.

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alwelch wrote:
Seems like an approved module is the way to meet FCC regulations. The Raven is not for use in a product as it is.

In my opinion the answer is almost always yes. You should use a pre-approved module.

However,
If you require a high performance module and a mid-to-high volume of production and you have the ability/money/time to design/produce it, then you might be better off rolling your own. The low cost modules on the market right now have inferior performance compared to the high end. The other thing about designing your own is that you can make it more efficient and flexible relative to your particular application. So it all depends...

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The reason that there is a good market for FCC (et al) type-accepted radio modules for OEMs is that, if unmodified, the end item doesn't need recertification.
To wit: the 802.15.4 modules that ARE internationally type certified. Few are certified in more than one country. Look before you buy. Digi has one of the largest lists, and note that the max power and occupied bandwidth vary widely by country, e.g., Japan's regs require special operating restrictions.

IMO: it's naive for a chip maker to NOT work with OEM module makers for widespread availability of approved modules. Compared to Freescale, TI, Ember and others, Atmel has fallen short here, IMO, esp. with the choice of Meshnetics in Moscow. Or they want design-wins for a mass market product incorporating their ISM band chips and that company bears the cost of cert. tests worldwide. That's OK for an automotive design win, but not for the hundreds or thousands of lower volume products, like home automation or SCADA.

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stevech wrote:
IMO: it's naive for a chip maker to NOT work with OEM module makers for widespread availability of approved modules. Compared to Freescale, TI, Ember and others, Atmel has fallen short here, IMO, esp. with the choice of Meshnetics in Moscow. Or they want design-wins for a mass market product incorporating their ISM band chips and that company bears the cost of cert. tests worldwide.

I'm not sure what you mean by this. Are you saying that Atmel FAEs are not doing their job in supporting their clients? Or are you saying that Atmel should help pay for the cost of design and certification of other companies products?

I believe that all the companies you listed provide reference designs and app notes for their ISM band silicon. These reference designs are intended to help Engineers get familiar with their products, recommended pcb layout, etc. They are usually not suitable for production-quality products and from what I have seen, do not have modular approval because they are not complete modules and therefore do not qualify for modular testing.

I don't really see where Atmel is falling short in that regard compared to any other producer of ISM band tranceiver ICs. Maybe I'm the one being "naive" here, but reference design, data sheets, app notes, and ocassional e-mail to FAE have always been enough support for me. I wouldn't turn away money if someone else wants to pay for testing though ;)