BLE MIDI kit dev blog

So I’ve done lots of cleanup. Getting the board into 3d helped me fit components and realize what didn’t work well.

I’ve added a rotary encoder at the top, and further isolated some of the local ground-planes so that the regular ground wasn’t coming nearby to ruin the party, the local ground planes for my high frequency devices now have pours under the component, but still only contact through the single shunt with a filter capacitor nearby.

I utilized the local ground for my charging circuit as well, and indicated the isolation in silkscreen. This is a pattern I’ve seen on some boards, where they keep some isolation on their power/charging side, so it seems prudent. The silkscreen is mostly indicative for any sort of bodges, (IE, don’t pull from here unless it is power related).

I cleaned up a bunch of the silkscreen locations, and standardized on a minimum font size that is legible (as determined from other test boards)

I’ve removed the pointy bits near the antenna cutout (they are now nice and smooth) and I’ve opted for two through-hole resistors for the charging circuit so I can more easily adapt to different batteries. I’ve also added silkscreen with the formula and example battery to charging profile parameters (to help with self-documentation),

The board is slightly wider now (about 5mm wider) which makes it a square 100mm x 100mm. This gave me room to spread out the buttons to provide some breathing room for the keycaps.

I realized my linear slide potentiometers, while probably fine, didn’t have plated holes (I put just regular holes) for the mechanical connections. Those have now been plated to allow me to solder them in place.

I found a bunch of tiny dimensional errors that, likely not critical, were incorrect, so I adjusted those to clean them up.

I’ve also added the boot mode button for programming.

All the components were re-numbered so that they follow a nice flow (and are roughly in the order of if you were soldering by hand and wanted to validate the circuit as you went along).

I refactored some of the mounting holes to give more options for case creation.

I’ve sent a prototype of these off to get things rolling.

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