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MRF24J40MA

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epa
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2009/07/31 01:47:07 (permalink)
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MRF24J40MA

Hi everyone,
 
I am planning to use Microchips MRF24J40MA 2.4GHz RF module for a task which aims to raed a gas sensor in real time. Can someone tell me what is the ranege i can go with this module with and without RF LOS ? are there any repeaters available (or mesh technology) for this module in order to increase the readable distance...... ?
 
further is there any rtecommended PIc microcontroller use with this module ? i am planning to use PIC 18F452....! AFAIK any MCU with SPI interface can use with this module ?
 
Thanks in advance.

Cheers
~ Epa
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    ericwertz
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    RE: MRF24J40MA 2009/07/31 02:31:46 (permalink)
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    You clearly haven't even read the first page of the datasheet, have you...

    Ultimately, you'll only ever really know if it'll work for you unless you evaluate it in your environment.  If you're in a flat cornfield, probably something like 100m.

    Depending on how many networking features you want it to support, you will probably need at least a 64kb flash part.  Perhaps 96kB or even 128kB.

    You really need to at least look at the marketing collateral, then look over the datasheet.

    #2
    epa
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    RE: MRF24J40MA 2009/07/31 03:05:23 (permalink)
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    Dear ericwertz..,
     
    thanks for your both replies....  exrtremly sorry about useless questions which i could found the ansewers from the Datasheet.. yes.. i read it again and found all i need at first page..... reason is i jsut take rough read at the datashhet and missed the most important lines..... cz i am just evaluating few products from Ti, Digi and few korean branded ones........... ok.. shame on me... :(..
     
    BTW i think this distance given 400ft is with RF LOS. that should be much low in a urban/indoor area which means w/o Line-of-sight.... so still my question exists that is it possible obtain repeating modules from Microchip.. ?
    #3
    ericwertz
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    RE: MRF24J40MA 2009/07/31 04:32:59 (permalink)
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    Everything that Microchip makes is on the website, or at www.microchipdirect.com.

    For the most part Microchip provides the tools and components for you to design your own products, and doesn't create products for endusers.  Digi does both, components and "drop-in" networking products and you can plug in and use pretty quickly, if you can't/don't want to do extensive development.

    Microchip leaves end-user products for their third-party and product partners.  So, no, they don't make dedicated repeaters, but someone might.  You could start looking in the "Support" section of the website where their partners are listed.

    Some types of modules will repeat if you run the networking code that supports mesh networking.  ZigBee and many of the proprietary mesh network protocols do this automatically.

    There are many, many choices of companies that do mesh hardware and software.  Sometimes it seems like too many... [8|]
    Some companies have 2-3 note demo/evaluation product that you can test with for $US200-400.  Too many of them want $US1000-1500 for 4-5 nodes minimum.  If your time is worth something, then any of these are probably the "best" ways to figure out what will work best for you.

    good luck

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    Kiwi Mike AZ
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    RE: MRF24J40MA 2009/07/31 18:07:19 (permalink)
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    Testing I had about 25 meters indoors (Depending on walls people etc)
    Outdoors I got 100 to 120Meters (100 meters was in a lighting storm)

    From what I have been told the new module the MB will get 350+ meters outdoors in between buildings... I have not been able to test this myself yet, but hope to in the near future when they have them available for sale.

    The 900MHz chip looks good as well, but is not in a module yet.

    Just did a class that lets you use the MRF24J40 or the MRF49XA parts seamlessly with MiWi or MiWi P2P
    By changing a #define's you can select either stacks, and either modules, and don't have to change any other software to do it!


    Mike
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    epa
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    RE: MRF24J40MA 2009/08/04 03:10:13 (permalink)
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    What is the module MB you are talking about mike ?
    Is it from same Microchip Technologies..? could you please explain it.......

    Cheers
    ~ Epa
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    Kiwi Mike AZ
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    RE: MRF24J40MA 2009/08/04 07:15:22 (permalink)
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    The MRF24J40MB is a +20dBm version of the MRF24J40MA

    http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en542228

    Has a larger footprint, but you can design you layout so both boards fit on the same PCB.

    Mike
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    synapsys
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    RE: MRF24J40MA 2009/08/04 10:26:50 (permalink)
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    Hi mimemike,

    Since the MB module is 0.2" longer than the MA module could you explain how you would design a PCB layout that accomdates both modules? The datasheet for each module indicates that the antenna should stick out from the edge of the PCB with a minimum 0.4" ground plane surrounding the remainder of the module. I can understand how you could make the pads wider so that either module could be soldered to the PCB but if this were the case than the MB module would extend 0.2" further from the PCB edge and that would mean 0.2" of the module would not have a ground plane next to it. I am in the process of designing a PCB for the MA module and would like to hear your thoughts on making it compatible with the MB module as well.

    Thanks,
    Synapsys
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    Kiwi Mike AZ
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    RE: MRF24J40MA 2009/08/04 18:27:57 (permalink)
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    The MB is wider and Longer.

    If you lay out the MB part first, then you can fit a MA inside that footprint with the same edge alignment
    Also if you do not mind losing a little gain on the MB part, then you can design the board for the MA part, and align the MB pads directly beside the MA pads.

    See picture attached of both options that I just quickly did.



    post edited by mimemike - 2009/08/04 18:29:05

    Attached Image(s)

    #9
    epa
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    RE: MRF24J40MA 2009/08/05 00:06:23 (permalink)
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    Hi mike,
     
    thanks for your continous support... But as you said and as per to the European transmitting power limitations MB module is not suitable for my application. Anyway I need to find out few code examples to for 18F PIC programming for ZigBee works. Found some codes in few design notes and like to have some more. Could you guide me to a any link which has more coding examples... ?
     
    And i posted a new link asking few more essential questions for my work.., here http://www.microchip.com/forums/tm.aspx?m=438729 . Could you please comment it with your experienced design ideas ?
    Thanks.
     
    - epa
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    synapsys
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    RE: MRF24J40MA 2009/08/05 06:05:04 (permalink)
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    Thanks for your thoughts Mike Smile

    Regards,
    Synapsys
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