MRF24J40MA Recommendations

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AtomSoft

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Hey guys just got a couple of MRF24J40MA board and wanted to ask since i have no clue on how to use em or which is best...

Zigbee

or

MiWi

????

Which is simpler heh...

Also do i really HAVE to use 1 of those 2? Or can i just pump out data myself ? Can i simple send out bytes of data and receive bytes of data?

I know i have to send out like a MAC address and stuff right?
 
Miwi P2P is the easiest. I have a couple of those and I started trying to port the MIWI P2P to the SAM7, but I never got it finished and now I'm using the much simpler RF12B modules. 2.4Ghz is pretty saturated around here anyway.
 
seems like a hard part to find heh... Ill take a look into MiWi since its easiest heh

Thanks For the tip....
 
Just downloaded: IEEE 802.15.4-2003
 
Well, MiWi was made by Microchip, so in running on a PIC with the Microchip-made transceiver, I'd suspect it'll be more trouble-free than Zigbee. The main reason I'd go for Zigbee would be compatability with other Zigbee products.

No, I don't think you can simply pump data. Reason being the MRF24J is not a simple serial link but a complete link layer, and that's in the hardware. I think overall that's a much better idea. And the software's available from Microchip for the PIC so that should be fairly straightforward to install. The stack implementation should be encapsulated in their code, so I think it'll basically be "pumping data" to the software anyways.

I have a pair here I need to get running soon. Should be fun. They've got some hella impressive capabilities for $10.
 
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yeah heh... im recreating the PICDEM Z board here since i have 2 18LF4620 PICs here i will test it the way they did... The only thing is the PICDEM Z board has a 4Mhz Crystal and i have on 10MHZ and 20MHZ crystals around... but i think i have a few 4mhz crystals on a board i can probably pull.

So ill be sure to post the progress on my blog... link is in my sig below
 
Zigbee is a mesh network and has a large stack that uses most of the memory on the PICDEMZ board.

If you want to do point to point stick with MiWi.

There is a bug in the Zigbee stack that will not let it work with a 10MHz crystal but there is a fix in the forum.

I built a few PICDEMZ like PCBs but left off the serial and switches. I used a resonator instead of crystal and caps. Processor pins come out to the card edge. The SMD temperature sensor is under the radio. It can be built as a SS PCB with 2 jumpers. Regulator is a TO-92 package.

The board to the left is an earlier version.

 

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im actually going to make a PICDEM Z light of my own heh I like yours tho...
I will take a look into the MCP1700 looks nifty and cheap heh

Product Search - microchipDIRECT

WOW those are expensive heh but heh... Anyway... im making my schematics now... to clone the PICDEM Z... the basics are in... tho and well heh its not much to add but some LEDs and buttons. really i wonder about the price....

 

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Very nice....... It's definitely time to get off the fence and start etching.

Here is an PICDEMZ ice cream sandwich, with a 16f688 in the middle. It takes an very abbreviated XBee approach of decoding ascii from the Microchip radio appnote.

 

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I am glad to see other members working with this radio.

@Atomsoft

I was fairly sure you would want to do you own design. That is why I did not upload the eagle files. I am using these to proto type more app specific boards rather then run the demos. The thinking is that a breadboard or 2nd PCB will provide whatever else is needed.

@nickelflippr

That is a neat/nice bit of work you have there. The etching is one more process to tinker with. I tend to get caught up in tool processes and that slows me down but I enjoy it.
 
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Heh these seem nice and fun once i can get at least 1 board made. This way i have 1 that is stable and can build the other to do what is needed..

Compact is the name of the game. Im going to try and make the board small as possible. This will reduce the final cost by a few bucks. I might even look into
the TQFP package... Just so i can reduce size further
 
I have a TQFP .5mm PCB in the works.

My plan is to offer a range of these Zigbee network boards to help fund my educational efforts. In addition to having some fun.
 
3VO:
Do you mean .5mm traces?, as the 18lf4620 TQFP pitch is .8mm. I am sort of surprised that someone hasn't come out with a XBEE look alike, in a more friendly .1" pitch dip module. If that's what you plan, then it should be well received. The XBEE 2mm pitch is cruel.

AtomSoft:
For me the TQFP is just manageable, I'd say go for it. Using 805 smt caps and resistors will tighten things up quite a bit too.
 
yeah i was thinking 0603 since i have some experience with them heh... those 0805 are larger correct?

If so i might just use digikey or mouser and order some 805 sized parts. Im making the design in DIP Form right now and it looks exactly like 3v0's board heh

Um... can someone point me to some SMT headers

EDIT: I mean to say FEMALE HEADERS...
 
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I've never been into the standard size SMT headers as they kinda defeat one of the purposes of SMT in that they take up more space, because they need a large set of pads to stick onto. Also I've never seen any that I would consider cheap.

Depending on what you are doing, you can edge solder standard headers if you don't want to drill holes. Just make SMD pads along the edge of the board.
 
I can do .8mm pin pitch. I am working with the PIC18F67J11 .5mm pin pitch. The 18LF4620 does not have enough ram to code the coordinator I have planned.

The artwork is OK from the printer but when it comes off the laminator I am getting a bit of distortion on a few pads. I could build as is but want to figure this out. Heat pressure (roller condition) etc.

@atomsoft
I would have sent you the eagle files if you wanted them.

3v0
 
AtomSoft:
The 805's are bigger than your 603's. They are handy because they span .1" pcb pads pretty well, and a big plus is I can sort of see them. Ebay has reasonably priced combo kits of 805 resistors and capacitors.

3V0:
O.K. right, you have mentioned the memory issue before on the '4620. For me a P2P, or maybe MiWi stack, on a much smaller part will be the goal.
 
The main reason for SMD/SMT headers would be to eliminate some VIAs ... think about it if headers are on bottom layer then a via is needed for each pin to a header heh correct?

Oh yeah and for newer designs i use Altium Designer
 
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