Hi all,
This has been cross-posted over at DT so I can get a broad section of views.
Now that I have my beamsprings humming along happily on USB, I wish to adapt my USB capacitive keyboard controller to my two Model Fs (a nice PC-AT and a battered but delightfully pingy 122-key terminal).
I've put together the layout pretty quickly:
However now I have a decision to make. You'll see that the actual guts of the controller take up a relatively small area in the centre. However in adding mounting holes I now have a lot of wasted space.
The four holes at the bottom (P3..6) are mounting holes for what I'll call the `standard' Model F controller (what's in my PC-AT and 122-key terminal). No big deal.
The two holes at the top are in (what I believe are) appropriate positions for the slightly shrunk Kishsaver controller.
In combining the two mounting holes we now have a lot of wasted space, and the PCB now costs twice as much from OSHPark compared with the beamspring controller. Overall size is still smaller than the original at 149.5mm x 42.5mm, but the extra board space on the bottom might pose an issue for Kishsavers.
Either I can make these extra mounting bits `snap-off' (and live with the extra PCB manufacturing cost), or simply have two separate board designs with appropriate mounting holes for each.
What does GH think? Can we forgo the mounting holes entirely and use some nice spongy double-sided tape-foam?
Also, so far I've made the assumption that there are only two types of detachable Model F controllers (not counting XTs or Bigfoots which have controllers integrated into the keyboard PCB itself). Is anybody aware of any other designs that I should take into account?