Been pretty busy lately trying to put together the initial prototypes for the FreakZ development platform which is also why it's been a little quiet on my blog. I had a very brief respite last week and then had to deal with a bunch of things. The parts that I had ordered from DigiKey got tied up in Japan customs. It turned into a painful ordeal where I had to communicate with customs via regular mail to provide detailed information on the parts, what I was going to do with them, the origin, and of course the cost in order to calculate import duties. Ugh...gonna need to get a lot more savvy about international trade if I'm hoping to sell some boards.

The board panels arrived the same day that my parts did which was kind of nice. After cutting out the boards and starting to assemble them, I realized that I had grossly miscalculated the effects of using a barebones PCB type of service. Not having the soldermask increased the difficulty of assembling the boards very much. It's very stressful when you have to doublecheck each solder joint to make sure you didn't bridge anything. The worst case actually occurred which was was a bridge between power and ground. This is the worst type of short to have because it's nearly impossible to find. It took me hours tracking it down and I had to tear off all the components from the board just to find it. It turned out to be a hairline solder bridge that was nearly invisible to the naked eye. I need to go over all the traces with a 10x magnifying loupe to find it. After that, I was very careful with the soldering iron and tried to avoid touching the ground pours on the board. It was like playing "Operation", that old game where you had to remove things from a body without touching the any sides. 

Needless to say, I won't be using Barebones PCB for prototyping anymore. The service is good and the boards were excellent quality, but the added time and stress from dealing with having no solder mask just isn't worth it. Also, the cost after shipping and the shipping time ended up being worse than using a service like GoldPhoenix which provides a solder mask and a silkscreen. 

I was pretty happy with the modular connector scheme. I think I made the right choice in using right-angled connectors because all the boards will be flush with each other. I was getting irritated at having multi-level boards, plus I needed to keep standoffs of varying heights. Having them all the same height looks more visually appealing and is easier to deal with in terms of parts. 

The breadboard peripheral was originally just for the Tokyo Hackerspace development board since we will be using that as a teaching platform. But after seeing it in real life, I think I'll be using it a lot for the FreakZ platform as well. It's going to be nice to be able to quickly prototype sensor circuits as well as other types, even just to get an understanding of the behavior. Since all the MCU inputs are broken out on the peripheral, it'll be easy to write up quick routines to read digital sensor values or feed them into the AVR's analog/digital converter. Also, since it's using the modular connector, I can swap them in between the FreakZ board and the Hackerspace board. 

Anyways, I finally got the boards assembled last night and need to start powering them up and testing to make sure they're okay. If things work on them, the next step will be to send the finalized gerbers out to a PCB house where I'll probably do a run of about a hundred boards. 

Here's a couple of pictures of the prototypes:

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