05.10.2015 - Microbook, mk 2 |
It would have been good for it to have an e-ink screen, to be thinner, the screen to be larger, etc.
Such was the feedback for Mk. 1, that i couldn't fulfill for a while.
Then, i found out that there are documented e-ink displays in open sale.
http://www.pervasivedisplays.com sells them, and they are not at all that hard to interface.
I got a demo board from them, and knew at once that this is the kind of screen Microbook needs.
Unfortunately, to fit the screen interface within it's own size was a task outside my home PCB etching capabilities.
| Thin traces. Very thin, very close|
At first, that was a show-stopper - what is the point of an open-source hardware project that can't be made at home?
But really, it's not that big of an issue, apparently.
So, i went to
the Dark Side PCBCart, and got a few boards made.
It was an interesting experience - i have gone over the design many times, checked the reference schematics for the screen interface several times over, looked closely at the demo board, simulated the charge/discharge circuitry, etc.
Still, the fact remained that i was sending PCBCart a board i haven't actually made and tested myself - that never happened before.
But it came out ok.
The display from the demo kit fit in nicely, and worked from the first try.
(Well, the second. Lesson learned - don't try to test things at 3am and sleepy - you WILL screw up even a blinking LED program, and spend hours looking for a hardware fault that doesn't exist.)
The result is a nice, flat package with a big, low-power screen.
I also added an USB charging port, in case the sun wasn't available.
The "perk" of the design - a solar panel on the back to charge it anywhere from free energy.
Might not look like much, but there are 4 of the Mk. 1 models out there with a much more power-hungry screens and no other charging option, that worked for years without ever running out of charge.
Under the panel, a typical li-po cell.
I wanted to put it under the screen, but they don't make cell that thin, apparently.
No idea how long it would last without a charge this time.
But i hope for years.
There are still a lot to tweak and a proper software to write (update times with the Mk. 1 FW are atrocious), so the design files will follow later.
|Wery nice! Are You going to share sources?
26.05.2018 19:30 - Evg
|Hi, are you available to work on some similar projects ?|
27.03.2018 05:02 - Wober Dane
|I actually thought about making something with this or 10.2" displays of theirs.
However i'm out of budget for the moment, and these things are expensive even without intercontinental delivery.
Not sure how much sense would it make - even 2.7" one alone cost as much as two Mk1 microbooks, and 7.4" one would be 4 times more expensive than that.
In other words, it would escalate from "easy DIY project" to "ridiculous".
Even Mk2 is already almost past the "makes sense" line, and is only there because 2.7" displays are common enough in various kits to be reasonable.
26.02.2015 02:36 - Artlav
|http://www.pervasivedisplays.com/products/74 - how about this one?|
25.02.2015 13:59 - Max
|Absolutely gorgeous. But, the commentary about larger display still applies: is there a chance to see mk3 (or macrobook) e-ink reader which is about 20 cm wide - so it fits in a4 paper easily. And, ideally, with some touch capabilities so there's no need to bother with soldering buttons on the side?|
25.02.2015 13:53 - Max
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