After a loooong weekend and sneaking in a few hours – Success with the keyboard layout dimensions!
There’s few tweaks here and there remaining to align things perfectly and also to add some nice Silk Screen artwork
And, how I got there!
Print off 1:1, Measure, compare and re-print. Iteration takes blimmin’ ages!
And, showing how the measurements compare by slotting in the PCB Layout print.
And Finally the bottom row – showing the edges where the alignment is almost perfect!
I doubt the layout has to be quite as exact as this – at the end of the day the switches i’m chosing to use have roughly 3x3mm ‘inserts’ to fit into a 5x5mm hole in the keyboard button, as long as the switch is positioned on the PCB within +/- 1mm, the insert’ll jam into the button just fine. Here I’m accurate to about +/- 0.2mm I’d say
Next steps…..Additional components and PCB revisions / additions needed to turn this into a USB Keyboard…..
There’s a few ways that this can be done – My preference would be a small additional PCB…….on the top right of the below image
My thoughts are –
Use the standard ‘matrix’ output 20 pin header and Be able to plug straight on a number of other modules – Namely all sorts of ardunios for Matrix to USB conversion.
Unsure how this’ll work but it’ll free up quite a bit of space
on the other hand it’ll make mounting a little tricker as i’ll need some sort of plug / socket combination – maybe a raspberry pi like 40 pin header ribbon cable, or some type of PCB mount header sockets, I’ll figure it out another time!
Next steps
Physical Switches – testing with a cardboard PCB
Test fit with a cardboard PCB
Routing
USB conversion
Software
And…The Biggy
Just how the heck to get the buttons off the plastic AND keep them straight and tidy……..I’ve some ideas there! Did I tell you I own a CNC, 3D printer and a KNK Zing vinyl cutter!, should be able to knock something up there 😛
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