[Tinkerphones] [Arm-netbook] Future case idea: subnotebook/PDA with QWERTY keyboard

Sam Pablo Kuper sampablokuper at posteo.net
Sun Sep 4 18:16:13 CEST 2016

N.B. I have cross-posted this email to the TinkerPhones mailing list,
because it appeared to be relevant to both the TinkerPhones list and the
arm-netbook list. I hope that this is considered acceptable by users of
both lists. If not, please reply to let me know, and accept my apologies
in advance. Thanks.

On 26/08/16 18:37, Sam Pablo Kuper wrote to arm-netbook at lists.phcomp.co.uk:
> It would be great to have a housing for the EOMA68 that is of a similar
> form factor to one of these devices:
> - DragonBox Pyra [1]
> - Openbox Pandora [2]
> - HTC Universal [3]
> or even:
> - HTC Dream [4]
> That is, an enclosure that can fit in a pocket, and has:
> - Hardware QWERTY keyboard

It might be naive of me, but my impression is that the hardest part of
making a housing like this is probably getting the keyboard right. So
many moving parts; such critical layout, tactility, and reliability

I figure there are two broad satisfactory options:

(1) Design and build keyboards using commonly available push-switches,
combined with PCBs and housings made from designs released as Free
Cultural Works.[0]

(2) Use off-the-shelf standalone miniature keyboards, at least for

Of these, (1) is preferable, but it appears to be the most work. The
Pyra and Pandora projects presumably invested much effort into creating
their keyboards. Sadly, they have not made the designs available as free
cultural works, AFAIK. (Besides, if I were making my own, I'd probably
want it to have NKRO, and to be able to be swapped out a bit like an
EOMA-68 computing card, so that the user could easily slide out their
QWERTY keyboard and replace it with a miniature version of the
Stenoboard[1] or suchlike.)

Therefore, in pursuit of (2), I made a spreadsheet with all the
standalone miniature keyboards I could find, in the hope that one or
more of them might be viable for cannibalising into an EOMA-68
subnotebook/PDA case, at least for an early prototype.

I don't currently know a good way to collaboratively edit spreadsheets
using only free software. (Maybe use something like PySpread and put it
in a Git repo? Or sign up to MyKolab? Anyhow, that's getting off
topic...) So, I used Google Docs. Blech. Anyhow, you can access the
sheet as a CSV file without having to run any JavaScript, let alone
proprietary JavaScript:


If you want to view the sheet in your browser, then you can do that
here, but this requires running proprietary JavaScript which, obviously,
I don't recommend:


One striking thing about the current market for *miniature* standalone
keyboards is that there's only *one* USB device I could find for sale:
the CarTFT MiniKey. The others use Bluetooth or proprietary 2.4GHz radio
for communicating with the host computer, and use USB only for charging
a battery.

2.4GHz is often implemented with very poor security (see Samy Kamkar et
al), and some Bluetooth keyboards have, at least in the past, also been
prone to keysniffing and keystroke injection. Maybe that has improved
since people like Mike Ossmann started alerting people to Bluetooth
vulnerabilities, but suffice it to say that I have no interest in using
a wireless keyboard.

Sadly, the USB keyboard (the CarTFT MiniKey) doesn't look very
user-friendly. It appears to have squishy keys, which in my experience
give poor tactile feedback; and it lacks Esc, Ctrl, Alt and Tab keys,
making it useless for Vim, Emacs, Bash, etc.

I don't know how viable it is to convert one of the more fully-featured
keyboards from wireless to USB (cabled) operation.

***Questions for the list:***

- Are you aware of anyone having successfully converted a miniature
wireless keyboard into a wired USB keyboard?

- Do you know of any existing designs for miniature USB keyboards that
are partly or completely Free Cultural Works (e.g. that provide KiCAD
and/or OpenSCAD files under a GPL license)?

Please post links/info if so.



[0] http://freedomdefined.org/

[1] http://stenoboard.com/

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