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I really want to develop on a gumstix with an e-ink display, but $3000 for a development board is a bit steep for me right now, especially since I just want to get a prototype out so I can see what the market is like.

As a work-around, this is what I have in mind:

  • Buy a Kindle
  • Buy a gumstix with a dev board
  • Hook up the Kindle display to dev board using clever soldering

This is what I want in the end:

  • Low-power, easy to read screen (text viewing)
  • Wifi-enabled device
  • More than 4 GB of persistent storage
  • Touch enabled device (I can get by without this)
  • Preferably color, but monochrome is ok

I am really intrigued by the persistence of the e-ink display without using battery...

Is it possible to use the e-ink screen with the gumstix? If not, is there anything else I should be looking into?

EDIT:

I think I can root the Kindle and install my own OS on it, but I won't be able to easily add parts to it (say USB ports, audio ports, etc). The gumstix is really the way to go.

Legal:

From what I read in the EULA, it is a violation to disassemble the Kindle, but the only thing they can do is revoke access to the Kindle Store and revoke use of any eBooks or services downloaded. There is no mention of penalties or fines for violating the EULA with respect to hardware. Since I am not developing this as part of a company, I don't think there is anything they can do legally.

Even so, I just want to know if it can be done with existing hardware and software. If I plan to market something with Kindle hardware components (which I won't), I'll definitely talk to a lawyer first.

beatgammit
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    I'm not so sure about the legality of buying a Kindle and rooting it, even if it is just to make prototype. If you are making a professional product, there is a chance you could get your company in trouble. – Ryan Apr 18 '11 at 12:34
  • I am not designing this for a company. I want to build this for myself and show it to potential investors, and if there's a market, I'll go ahead and buy the dev board. – beatgammit Apr 18 '11 at 16:30
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    @Ryan - I think it's perfectly alright to root it: if you buy it it becomes your property, you can do with it whatever you like, despite what Amazon may say (see also Apple). You may have trouble buying the screen from Amazon's supplier, though. If it was designed for (and the design paid for by) Amazon, it's unlikely that Amazon let others parasite on their investment. – stevenvh Apr 18 '11 at 16:58
  • @stevenvh From what I can tell, it's just the [E-Ink Pearl](http://www.eink.com/sell_sheets/pearl%20sell%20sheet.pdf) from E-ink. They may have modded the connectors, but I have a soldering iron for than =) – beatgammit Apr 18 '11 at 17:14
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    For personal use, I don't think there is a problem with rooting a Kindle. However, if you take an existing design, and hack it to make a new product, you are going to run into copyright issues. I'm not sure if you can get in trouble for hacking the equipment for a professional prototype, but I would be careful. – Ryan Apr 18 '11 at 18:13
  • @Ryan - Yeah, I understand the risks. I just want to know if it's possible, and if so, what resources I could look at to get started. – beatgammit Apr 18 '11 at 18:17
  • I don't see the interface between the screen and host documented anywhere. How do you intend to reverse whatever protocol they're using? – Adam Lawrence Apr 27 '11 at 16:20
  • @tjameson - Re: Designing for a company - It sounds like you *are* designing this for a company. Even if the company doesn't exist yet, Amazon's lawyers can still find out about your initial prototype and come for your company once it's made some money. That would suck. – Kevin Vermeer May 04 '11 at 15:40
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    @reemrevnivek - If I can find out a way to do this, I'll talk to a lawyer about the specifics (my cousin does litigation, and I'm sure he has friends who've dealt with stuff like this). – beatgammit May 07 '11 at 22:48
  • @Madmanguruman - AFAIK, the Kindle runs Android or something like it (definitely Linux), so if they made kernel changes, they'd have to be open source. If not, I can just steal the binaries. Or I could write my own. I just need to get the screen on the gumstix, software is the next battle. – beatgammit May 07 '11 at 22:51
  • @tjameson - Get the lawyer *before* you invest time and money, not after. – Kevin Vermeer May 08 '11 at 03:37
  • @tjameson - I doubt that they'd have to customize the kernel, most likely just make a device driver (loaded separately) which would have no legal obligation to be shared. – Adam Lawrence May 08 '11 at 19:24
  • my understanding is the nook is more hacker/developer friendly than the kindle. The nook is android based. Buying and tearing a kindle or nook or any of them apart to get at the display to hook to something else should not be a problem. buying a car to get a set of tires. You might not be able to get programming/datasheet info on the kindle or nook display so it may be a total bust. If you are trying to reverse engineer kindles drm or software or something like that that is a different story. – old_timer Jul 04 '11 at 05:00
  • does the prototype have to be an eink display? Can you create/use a simulator on a desktop? Or an lcd panel, something easier to come by. – old_timer Jul 04 '11 at 05:04
  • @dwelch- I'd like to see how responsive it is. I'll run some basic, automated tests to see if a touch-enabled display would be feasible. I don't need anything fancy, just simple buttons. – beatgammit Jul 04 '11 at 06:31

1 Answers1

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Get yourself a chinese ebook reader running linux.

Go look on ebay. "ebook linux"

I don't know how to root the one commonly sold with a wifi and keyboard yet, but it is definitely sold as a linux machine.

I own an earlier model without keyobard or wifi ( I wanted a book reader.) It in an ARM CPU, runs linux, takes 8Gb memory cards and internally the PCB has pads for 9 pin serial port, vias for the 9 pin serial port, SIM slot, Ethernet jack ( and pads to attach the Ethernet chips) sound in, input ADC pads next to it, and pads for a microphone. Looks like the development team used their dev layout with less parts loaded. I'd bet the parts used were the cheapest supported by linux/arm. The screen controller is a standard e-ink interface part too; so in theory I can build my own bootable linux image for it.

My experience is that the bootloader shows the GRUB line on one line of the display just as it boots. A serial console connection ( indicited by the presence of the vias for the serial as well as the pads) would allow me to interrupt boot and redirect init=/bin/sh

So then all I need is to mount the removable media ( if it hasn't automounted!) and copy the existing system image off to removable for autopsy and alteration.

Tim Williscroft
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  • I guess that is a pretty good option, and [this](http://cgi.ebay.com/fashion-E-ink-6-inch-wifi-ebook-e-book-reader-Linux-bp-/120711327031?pt=US_Tablets&hash=item1c1af4ad37#shId) one looked pretty good. Do you think it would be decently easy to get a serial connection or something to one of these? I doubt the documentation is any good (and probably really bad grammar). – beatgammit Jul 04 '11 at 06:35
  • Good luck finding the source code for that. I don't think there is any hope of forcing GPL compliance in china. – Connor Wolf Jul 04 '11 at 07:59
  • @Fake Name, I dunno if I'd _want_ the sources, these machines are really very standard under the hood – Tim Williscroft Jul 04 '11 at 22:45
  • @Tim Williscroft - Not on a hardware level they aren't. There are all sorts of clock trim registers for the graphics driver section of the CPU, and all the buttons are implemented wither through a software driver or hardware key-matrix scanner, and you need to know how the keys map to what letters. Also, there are several ways you can have the system boot, and assuming it's using uBoot, there are a couple of ways to store the boot image on the local flash. Sure you *could* reverse all the interfaces and how the thing is wired, but just getting the source is much easier. – Connor Wolf Jul 05 '11 at 08:08