Good news everyone! I'm working on a version 2.0 board that operates over i2c using the TCA8418. This will be my first project using SMD parts and so far so good.
For switches I picked the EVQ-Q2B03W. They are more pricey than your typical tactile switch but are worth the cost in my opinion. The datasheet says they require 0.5 N of force to press, are 3.1 mm tall and are rated at 2,000,000 presses. They are VERY light touch, it really doesn't require much more force than just typing on your phone screen.
It breaks out all the usual bits and includes a JST-PH connector for i2c that is compatible with Adafruit's PyBadge and PyGamer.
Next steps will be:
- Seeing if this will work on raspberry pis without any other hardware. Note to self: checkout how the Malti project did this.
- Write an Arduino library (mostly done)
- Write a Micropython/Circuitpython library
- Look into getting them manufactured professionally. It took me about an hour to pick and place by hand and reflow.
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This is great. I've got a hyper pixel square on my rpi portable. more usb then for other stuff
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Interesting. I happened to pick the exact same switches for a little sequencer/drum machine/synthesizer project I just started. For the same reasons - light to touch.
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Hi! Very nice design. Where can I find schematics for this V2 version? I'm not sure where to connect INT and RESET pins. Thanks.
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Very nice, have you seen this smaller MEGA328P I2C keybaord M5Stack CardKB - https://m5stack.com/products/cardkb-mini-keyboard
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where do i buy this
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