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Newbie - Some questions on Launchpad EXP430G2

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Hi All,


I am using the EXP430G2 with AIR Booster pack to build a kit to remotely monitor an oil storage tank and I have some general queries which I hope you can help with.


i) Any advice/pointers on enclosures (indoor & outdoor) to house the Launchpad and/or the AIR board


ii) any alternative to the 32K crystal supplied with the Launchpad - this is an SMD device and tricky to solder. The board looks to be holed for to take a larger device- any thoughts welcome


iii) any pointers on information on how to use the emulation feature with Energia


Thanks in advance.



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I know it looks intimidating, but the crystal isn't that hard to solder if you hold it in place with a piece of electrical tape.  There are instructions here for soldering and testing that I found helpful - http://justinstech.org/index.php/2010/07/19/msp430-launchpad-dev-kit-how-too/- I followed those when I was extremely new at soldering and was able to do it without too much trouble.  You could buy one of the can-type crystals as well - I believe the included crystal requires 10pf capacitors, but the capacitance on the crystal pins is configurable so that's not a big deal.


If you've got access to a 3d printer, there is a nice bumper design available that I've used several times.  Pretty much any project box is fine for inside use.  I've heard of people using electrical boxes from the hardware store as outside enclosures as it's easy to find waterproof ones.

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What he said about soldering the crystal. I would also suggest using paste rather than wire solder form. Then you can hold the component down with a dental pick or a toothpick while heating with your iron. This reduces the risk of moving it, as tape won't hold it against a twitch with the iron tip.


I would not use a different crystal if you want reliable operation. Well, ok, maybe I would, but I don't recommend it unless you have all of the data for the crystal you use. Don't forget that the board and lead capacitance was designed into the LP for the supplied crystal, and you will need to compensate either with the internal programmed cap selection or using external caps.


Outdoor enclosures were discussed a number of months ago, but I would summarize with-- Unless you pot it solid in waterproofing compound, moisture WILL get in. You need a way for it to get out. Other than that, anything from a fancy custom box to a blue plastic project box should work. The cast aluminum outdoor outlet boxes are a nice size and have standard covers available. Better designs are those like used for optical fibre internet connections. The covers aren't gasketed, but the opening on the face of the box has full guttering like a well designed car door. The boards are mounted vertically, and they are well vented on the bottom, as well. If you don't believe moisture will get in, I will note the outdoor lighting I replaced a few years ago at one job. Weathertight boxes, with gaskets and all. Standard fare in the US. Pulled the cover plate off and there was 4 or 5mm of standing water in the bottom of the box due to the lip around the edge. The gasket was saturated as well. Reason the light failed was that one of the connections was pushed all the way down tot he bottom and was in the water. The other wire nut was oriented open up (wire ends pointing down) and was also full of water. Corrosion did things in.

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If you have a pair of fine tweezers you can also try this:

- Apply some [a small amount] solder to the ground pad with the iron.

- [optional] apply a bit of flux to the cooled solder from above.

- Place the crystal with the tweezers and touch the iron to the crystal case and the ground pad and let the solder flow.  The crystal should sit down into the solder blob.  The crystal should now be 'tacked' in place.

- Solder each leg.

- Have a drink of your choice.  :D



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