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Project Help and Ideas » Wireless modual tx rx

October 18, 2009
by Farmerjoecoledge
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I got myself a couple bluetooth mini wireless transceivers and looks like i need to alter some code. Bare with me but this is something that I thought would just work and i've realized i need to change some code or write some code or if i'm really lucky one of you code greats can whip something up.

So now i'm not 100% sure if my wiring is ok. The contacts are a whole 1mm in size, in other words almost impossible without the right board to mount the chip on. I made one out of a business card.The status light will light and the array is picking something up but it's not displaying any text.This is where you come in. I have the bluetooth client installed and it's found my modual so i choose send file but now what kind of file? So the transceiver is ttl and just changing the extension to .ttl is not enough. My guess is there needs to be something added to the uart or i need another listener. I'm hooking the tx to pd1 and rx to pd0 so those two wires are to me the same as the yellow/green of the programmer. I got one very basic wiring drawing with the modual and only says to hook the 5 contacts, vdc gnd tx rx and status. Hope your following me i think i'm lost, this is just simple wireless data transfer but as i'm finding out this is not a computer sending files transparantly to a pda this is a computer trying to send a data feed wirelessly to a display via bluetooth dongle. No big deal, right? Well i'm thinkin it can be done but that's all, the rest is up to you.

And then someone can tell me what other devices(besides cells, pda's etc)that take a tx/rx feed.

fjc

October 19, 2009
by rusirius
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I'll read over the rest later and see if I can be of any help, but in regards to the chip... Are you saying this is a 5 or 6mm surface mount chip? Like a QFN package? If that's the case, it's almost impossible to reliable work with WITHOUT making a breakout board... If you have a good laser printer I've had pretty good success making them.. Get (a GOOD quality!) laser transfer paper... Create the design in eagle or something similar and then print it out and transfer to PCB... Etch it... The easiest is "solder paste" but I've also had success with just pre-loading the pads with regular solder... Bake in a toaster oven at about 165 and the chip will settle in nicely... I always just make a simple breakout board that breaks the pads out to regular .1 spacing...

October 19, 2009
by Farmerjoecoledge
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http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=300348350118

Here's the link to the modual. Looks way bigger than it is. So what does "breaks the pads out" mean? Would you be using the solder paste? The way i've got mine is glued to a business card with presoldered wires just touched onto the tiny leads and fixed so they don't move. If i take the power and touch it on the tx rx leads the light will light so that says to me i've got a complete circut.

As for the uart i found some code in the 168 data sheet that looks like what i need but i can't run it. My programmer is double red and won't connect. I mistakenly zapped it with 12v. The chip is ok but the programmer isn't. Anybody know if it can be fixed. I already uninstalled reinstalled the drivers to no avail.

October 20, 2009
by rusirius
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I can't remember the exact package name of that off the top of my head... It's very similar to what I was thinking you had, but the good news is it's slightly easier to work with... Still don't take that the wrong way, they are NOT easy to work with... The good news is you have "leads" in a manner of speaking, they aren't buried under the chip like QFN, (that might be QFL now that I think of it...) Anyway....

If I understand you correctly, you have the chip glued to a piece of paper (card) and just have wires "touching" the leads and also glued in place... Chances are you do not have good connections on some of the leads...

By "breaking the pads out" what I mean is ... well... take a look at this... Here's a small one I did for another project I was working on... It's got some extra stuff on the board, not just breaking each pin out seperately, but it'll give you an idea...

breakout project

In the center is the surface mount chip... Each "pad" is broken out to a normal "through board" pad.. (i.e. the center gets drilled and a "pin" is stuck through and soldered... That way it can be plugged into a breadboard, connected via clip leads, etc...

What I'm getting at is, working with surface mount stuff is difficult, but not as difficult as you might think... But if you don't get a reliable connection you'll never know if it's the connection or something else... If it's surface mount and it's not soldered, chances are you don't have a reliable connection...

October 20, 2009
by rusirius
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also, one other thing to note... Some surface mount chips have a "pad" under them that is usually connected to ground... In some cases this MUST be connected for the chip to function...

October 20, 2009
by rusirius
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The other good news is that chip has the antenna built in... That's a big plus as you won't have to try to calculate and etch something semi-reliable on the PCB itself... Hell, now that I think about it I might just have to pick a few of those up to play with myself.... ;)

October 20, 2009
by Farmerjoecoledge
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Very good. That makes things clear. I was guessing when i mounted it on a card, the info on the net is very vague. I sort of did the same thing with stripped wires, but your right no way to be 100% sure unless i spend 1400.00 on a test system. I'm shut down now until i can get another programmer but these people say that this wireless modual can be incorporated into just about anything. I'm thinking what they mean is via ic, tx rx and code. Just puzzled, all i want for now is to send a feed transparently to the array. But for my future toy's i'm not sure how it all comes together yet. If you get yourself some of these things that would be great, a new adventure, between the two of us there might be a rainbow with real gold. ;)

October 20, 2009
by mikedoug
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Yes, and that rainbow should come in the form of a library. :)

October 21, 2009
by n3ueaEMTP
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So I picked up one of these Bluetooth modules from eBay, it arrived yesterday, then I saw this thread. Soldering is not one of my better skills. So I called my old friend Mr Google. Here is where he steered me:

http://www.sparkfun.com/commerce/product_info.php?products_id=8550

It's a little pricey, but if your not into building or soldering your own breakout board, this might help a bit.

October 21, 2009
by Farmerjoecoledge
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Well that makes a whole lot more sence. I really didn't consider the leads being so tiny, i was fooled by the image. So yeah, i looked for one of those breakout boards for my particular chip, that's like crazy and this particular one has the modual mounted,which is the way they all should be, and mine isn't, which is turning out to be quite a "etchie" ride.

Like do people by thousands of these things at that price? Where do you add a markup?

I found a conductive pen locally so that's going to make my life a whole lot easier. Oh, and by the way they say to hook it to a computer is totally strange. That's no more than a dongle, I think :|. The issue with my modual is it's got to be able to "pair" by keypad to the computer via bluetooth dongle. Which to me it already has by being recognized by the software. But no connect at the same time,don't figure. So i can't do dick with the uart until i get another shifter board and i'm in Alberta, 6wks minimum, Bummer. And...If library is a rainbow then that's one "Humugus" color blast....for a lack of something intelligent to say.

October 21, 2009
by rusirius
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Don't get too excited by the conductive pen... If it's anything like the older ones I'm thinking of, (used to be available in "paint" form) they are more for repairing a trace than anything, and even then it was pretty sketchy at best... I guess what I'm getting at is, rather it be wires just "touching" the pads, or the pads just sitting on a conductive trace, it's still just not going to be "right" unless it's soldered...

October 22, 2009
by Farmerjoecoledge
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Isn't that what they mean by "conductive" I went looking for solder paste and found this stuff. So what do you mean it not solder. It's your idea, also how would you presolder the pads, i presoldered the wires and with them fixed into the cardboard i touched them to the contacts (pads) they're solid on there so to me that's a good contact to a pad. So they are soldered now and the bluetooth software on my comp recognizes the modual it just won't connect which to me don't make no sence at all.

October 23, 2009
by Farmerjoecoledge
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http://www.curiousinventor.com/blog/54 So rusirius i found this site, now i know what you meant by the "pads". That's your qfn and conductive "ink". I'm sure these guy's just make this stuff up as they go along. Dam good instructions too, like how do you drill a square hole? But i get the picture.

So you seem to have misunderstood me when i said "touched" to the leads. That was with a soldering iron, so as not to lose the solder on the wire. It was tricky just getting the right amount on. Also i found that i fried my chip too with the 12v. Strange, it was running fine and then quit completly after the shifter quit. I got an excuse but who cares, right? But once i'm back running i got some stuff to do with the usart that should get the wireless up and running. We'll see you then. Mission RX TX.

January 25, 2011
by Jalex
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That's does sound like fun. I think I want to get another Micro and experiment getting them to talk to each other. I also like to play around building RF links so it would give me an opertunity to play there too. I have one I built sending and receiving music from my mp3 player and it has a pretty good range of around a 1/2 mile. I guess I can just modulate the TX on one and pull in the Rx to the other. right?. I have also built trancievers and that could be even better.

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