%(qi-html-head)s
%(qi-html-body-top)sOf course, not everything went quite as planned. I found a number of issues, fortunately most of them small: https://gitlab.com/anelok/anelok/blob/master/hw2/ERRATA I'm not done yet with design testing, so this list may still grow. There are also a number of configuration choices and deviations from the schematics: https://gitlab.com/anelok/anelok/blob/master/hw2/BOARDS Most of the deviations were caused by me not having the right part - usually some resistor - at hand, and should have negligible effect on the overall performance of the prototypes. I omitted the power consumption optimizations (configuration choices) for now. It'll be easy to test them later. So far, so good. However, ... I found a rather major blunder: I placed the footprint for the OLED connector 1.9 mm too far to the right, and didn't notice until I had the two prototype boards already made. One can see it in this picture: http://downloads.qi-hardware.com/people/werner/anelok/tmp/mk3-running/shift-oled.jpg The OLED sits on the top of the case instead of going into its cavity, and while the FPC (flexible printed circuit) connecting the OLED flexes nicely in the Y and Z direction, it will not budge in the X direction. Moving the OLED opening in the case would eliminate the "bridge" between OLED and buttons, and the buttons would then be free to fall out - something they already enjoy way too much with things as they are. I solved this by shifting the whole PCB, right into the left side wall. The tweaked case is on the left, a normal one on the right: http://downloads.qi-hardware.com/people/werner/anelok/tmp/mk3-running/shift-pcb.jpg Fortunately, the wall is 2 mm thick, so the PCB only looks odd there but doesn't stick out. Shifting the PCB caused the LED to end up left off the center of the buttons. The shift also means that the USB connector is too far from the right wall. To still be able to connect to the board while in the case, I grew the USB hole to accommodate also the overmold of the plug. A "normal" case is on the top, the tweaked one at the bottom: http://downloads.qi-hardware.com/people/werner/anelok/tmp/mk3-running/shift-usb.jpg I also had to trim the cylinders that hold the screws, and one of them gets too close to the inductor, transferring mechanical stress. You may have noticed the likely consequence in http://downloads.qi-hardware.com/people/werner/anelok/tmp/mk3-running/teardown-bottom2.jpg Fortunately, the inductor also works without that corner. Last but not least, I moved the "nipples" at the bottom of the button caps such that they still touch the centers of the tactile switches. The proper solution will be to correct the placement of the OLED connector in the layout for the next board revision. - Werner