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Eagle Eagle Eagle Eagle

Posted 2012.06.22 9.25 in Computers/Internet/Technology, Hobbies

You know how when you get hooked on something new, it’s all you can think about? Like drawing schematics and routing traces on a circuit board? For the past week that’s almost the only thing in my head.

When I close my eyes I see a maze of red and blue lines, green dots, and skinny beige criss-cross lines.¬†For those who aren’t familiar, that’s basically the default colours in Eagle for top traces, bottom traces, vias, and unrouted connections.

The freaky thing is, routing traces is fun! Like solving maze puzzles. You need to get this signal from here to over here. But you can’t cross any of the two dozen lines in between. And you can’t go outside the borders. And you can’t touch any lines – you can’t even get too close to any other lines.

So you snake up and down and left and right in between the lines, and when you’re completely blocked you dive down to the underside and weave around the lines on the bottom, then you pop back up again when the bottom is blocked, and finally you get to where you need to be!

And then you do that a hundred more times! And each time is harder than the last, because each time you route a trace, that’s one more trace that the next one has to avoid, and less overall space remaining available on the board.

So when the game finally ended, I had routed all my required signals, then I routed some extra pins, then I routed every last available pin on the microcontroller – even the ones that I had thought were totally trapped, I was able to find ways to break them out too.

This was all done by Tuesday – at that point there was nothing left to route, nothing left to tweak. So I spent another couple days just looking at it – admiring the patterns, and trying to find any flaws or mistakes.

Last night I finally submitted the designs for fabrication – using OSH Park’s service. They even gave me a rendering of what the board’s expected to look like:

Component Side

Solder Side

The lower part of the board with the buttons and battery connector is designed to be cut off – so it’s really two boards in one. This allows me to test it all in one-piece on the workbench, then separate the two parts for mounting on the leather bracer.

The Mark II version of the ISEB6 will have a whole lotta upgrades by the way… totally different uC, more sensors, more functions and features. It’s going to be awesome. So awesome that the PCB will be purple.

Yeah, that’s how awesome it will be!

Thermostat V3 Schematic

Posted 2012.06.19 9.45 in Computers/Internet/Technology, Hobbies

Here is a schematic for my Thermostat V3. It’s something of a ‘block diagram’ as I did for the ISEB6 layout, as it is another project that was mostly assembled from off the shelf modules.

You can download the PDF version here.

I have omitted the lux / luminosity sensor in the above schematic, because it’s not working very well and I find it’s fairly pointless. I’ll likley remove it from my thermostat next time I’m doing work on it.

For something of a BOM and assembly instructions, please download the zip file that was linked in the original Thermostat post.

Cheers!

Pow! Schematics!

Posted 2012.06.14 17.32 in Computers/Internet/Technology, Hobbies

Ok so Eagle is tough and the learning curve starts off very, very steep. But it seems like if you can get past the first 2 hours, it suddenly tapers off after that.

(Or click here for PDF version)

To get the above schematic to come out, not only did I need to figure out how to make a schematic in Eagle, but I had to make my own parts library and create four devices – the Pro Micro itself (as a discrete device rather than its own board and schematic), the OLED board, the compass module, and the Lilypad LED boards.

The reason I did this rather than laying out all those individual components was that I’ve assembled the ISEB6 out of these boards. That’s what it is. So it didn’t make sense to chart out the separate bits that go into each board – just get the boards. Or if you want to look at their schematics, get them from the source (Adafruit, Sparkfun.)

Note that 3 modifications were made to the Pro Micro board directly: the diode D2 was removed, which cuts the connection between UVCC and RAW. This prevents the LiPo from being exposed to 5vdc when a USB cable is connected. The Amber and Green LEDs were removed and hookup wire soldered to them, to connect to the two Lilypad LED panels. Oh and I removed the red power LED since it wasn’t needed. 4 modifications, then.

So if you’re looking to reproduce the ISEB6 yourself, hopefully the schematic alongside the build notes and the code (available here) should be enough.

Finally – I am already working on a Mark 2 version of the ISEB6 which in fact will do away with the Pro Micro board, and will have its own PCB (hopefully) allowing me to make it all neat and tidy and eliminate the rats-nest of hookup wire that forms the backbone of the current ISEB6.