External keyboard with a kindle

[RV987789]

Hi!
I want to know if is there some possibility of type with a normal keyboard in a kindle (or another e-ink device)? I mean, for example, to install a linux and then i connect an external keyboard?
I hope to be clear
Sorry for my english!

[geekmaster]

You can get external foldable keyboards for PDA pocket computers that use serial I/O on ebay for about $5 to $10. Do not get a keyboard that uses BlueTooth.

The kindle 3 has the serial I/O jack available at the lower slot in the left edge, and there are instructions on this forum how to make a connector and cable for it. Because the keyboard does not supply power, you can get power from the upper slot in the left side, but the bottom connector mus be adapted to short the bottom two pins in the lower slot to turn on battery power to the upper slot.

Other kindle models have the serial connector inside and require opening your kindle to access the serial port. There are kindle opening instructions for the different model in this forum and elsewhere as well. You might be able to locate a source of battery power inside the kindle as well, but this requires some level of electronics expertise. You could also connect an external power source (batteries or power supply).

Depending on what model keyboard you have, it may be necessary to buy or build a level-shifter circuit to convert between different TTL voltage levels. This can be done with two resistors and 3 diodes (or less). You can build something fancier with transistors, or you can buy a ready-made level shifter IC or circuit.

You also need software to configure you kindles serial port to use the same speed as your keyboard. Some keyboards need 9600 bps.

Unfortunately, this is an software and electronics hacking job. But hey, if you feel up to it, go for it. I bought some of these keyboards to use with my kindles. I will write whatever software I need WHEN I get around to that project (currently rather low priority). I will post my results back to this forum when that happens.

Good luck with that!

[RV987789]

Originally Posted by geekmaster

You can get external foldable keyboards for PDA pocket computersthat use serial I/O on ebay for about $5 to $10. Do not get a keyboard that uses BlueTooth.

The kindle 3 has the serial I/O jack available at the lower slot in the left edge, and there are instructions on this forum how to make a connector and cable for it. Because the keyboard does not supply power, you can get power from the upper slot in the left side, but the bottom connector mus be adapted to short the bottom two pins in the lower slot to turn on battery power to the upper slot.

Other kindle models have the serial connector inside and require opening your kindle to access the serial port. There are kindle opening instructions for the different model in this forum and elsewhere as well. You might be able to locate a source of battery power inside the kindle as well, but this requires some level of electronics expertise. You could also connect an external power source (batteries or power supply).

Depending on what model keyboard you have, it may be necessary to buy or build a level-shifter circuit to convert between different TTL voltage levels. This can be done with two resistors and 3 diodes (or less). You can build something fancier with transistors, or you can buy a ready-made level shifter IC or circuit.

You also need software to configure you kindles serial port to use the same speed as your keyboard. Some keyboards need 9600 bps.

Unfortunately, this is an software and electronics hacking job. But hey, if you feel up to it, go for it. I bought some of these keyboards to use with my kindles. I will write whatever software I need WHEN I get around to that project (currently rather low priority). I will post my results back to this forum when that happens.

Good luck with that!

Thank you very much for your response!
Unfortunately, I dont be so good in electronics jobs, but I have a friend wich can gives me a help. I will ask him with your indications.
Anyway, I still searching for the most effective and easiest solution, so this post is still open.
Thanks again!

[ixtab]

This may be a no-brainer, but couldn't one try to simply attach a normal USB keyboard? I'm sure there are adapters from "normal" to Micro-USB. Probably a bit of other fiddling is required (like configuring the USB port correctly, not sure if that's possible... I'm an idiot when it comes to electronics), but at least the kernel of the KT has the usbhid.ko modules lying around.

Or am I blatantly missing the obvious?

[geekmaster]

Originally Posted by ixtab

This may be a no-brainer, but couldn't one try to simply attach a normal USB keyboard? I'm sure there are adapters from "normal" to Micro-USB. Probably a bit of other fiddling is required (like configuring the USB port correctly, not sure if that's possible... I'm an idiot when it comes to electronics), but at least the kernel of the KT has the usbhid.ko modules lying around.

Or am I blatantly missing the obvious?

The external USB connector is only used for connecting to a host PC. There is an internal USB port that supports OTG (On-The-Go) which can be used in host mode to connect to USB devices such as a keyboard (or even a USB hub for multiple devices). There are two potential problems making it difficult to use:

1) You need to open the kindle and solder in some wires.

2) If you have a 3G modem installed, the USB port is used by the modem.

If you have a wifi-only kindle, the internal USB port should be available for your use, but you would need to configure it and install a device driver.

Another possibility would be to connect a USB bridge device to the external USB jack, such as a small microprocessor (Arduino or whatever) that acts as a host and communicates with the kindle as a device. It could also connect to a keyboard or other devices and share that with the kindle.

Because the kindle is not a host, it does not supply 5v power to the external USB power pins, so devices would need to be powered by an external power supply or battery pack.

So, maybe it is not so blatantly obvious after all.

EDIT: The above information was obtained from early posts by yifanlu and others. After reading the Freescale iMx.50 reference manual, I discovered that the host-only port is internal, and the OTG port is external. So a USB keyboard CAN work plugged into the external USB port (but needs software support).

[RV987789]

Originally Posted by geekmaster

The external USB connector is only used for connecting to a host PC. There is an internal USB port that supports OTG (On-The-Go) which can be used in host mode to connect to USB devices such as a keyboard (or even a USB hub for multiple devices). There are two potential problems making it difficult to use:

1) You need to open the kindle and solder in some wires.

2) If you have a 3G modem installed, the USB port is used by the modem.

If you have a wifi-only kindle, the internal USB port should be available for your use, but you would need to configure it and install a device driver.

Another possibility would be to connect a USB bridge device to the external USB jack, such as a small microprocessor (Arduino or whatever) that acts as a host and communicates with the kindle as a device. It could also connect to a keyboard or other devices and share that with the kindle.

Because the kindle is not a host, it does not supply 5v power to the external USB power pins, so devices would need to be powered by an external power supply or battery pack.

So, maybe it is not so blatantly obvious after all.

Ok, so now all is clearer. nIts not so hard but it's not so easy...

[multiprose]

Originally Posted by geekmaster

You can get external foldable keyboards for PDA pocket computersthat use serial I/O on ebay for about $5 to $10. Do not get a keyboard that uses BlueTooth.

The kindle 3 has the serial I/O jack available at the lower slot in the left edge, and there are instructions on this forum how to make a connector and cable for it. Because the keyboard does not supply power, you can get power from the upper slot in the left side, but the bottom connector mus be adapted to short the bottom two pins in the lower slot to turn on battery power to the upper slot.

Other kindle models have the serial connector inside and require opening your kindle to access the serial port. There are kindle opening instructions for the different model in this forum and elsewhere as well. You might be able to locate a source of battery power inside the kindle as well, but this requires some level of electronics expertise. You could also connect an external power source (batteries or power supply).

Depending on what model keyboard you have, it may be necessary to buy or build a level-shifter circuit to convert between different TTL voltage levels. This can be done with two resistors and 3 diodes (or less). You can build something fancier with transistors, or you can buy a ready-made level shifter IC or circuit.

You also need software to configure you kindles serial port to use the same speed as your keyboard. Some keyboards need 9600 bps.

Unfortunately, this is an software and electronics hacking job. But hey, if you feel up to it, go for it. I bought some of these keyboards to use with my kindles. I will write whatever software I need WHEN I get around to that project (currently rather low priority). I will post my results back to this forum when that happens.

Good luck with that!

thank you for the response geekmaster. you sound extremely knowledgeable.

could you post the link to the instructions on this forum how to make a connector and cable? i couldn't find it through the search. thanks.

[RV987789]

Originally Posted by multiprose

thank you for the response geekmaster. you sound extremely knowledgeable.

could you post the link to the instructions on this forum how to make a connector and cable? i couldn't find it through the search. thanks.

+1
It would be nice to see how much difficult its to make it!

[hawhill]

Note that it doesn't stop there. If you follow geekmaster's knowledgable advise (I really like the hacking spirit in these forums!), you'd have a keyboard connected to your kindle and both devices would be able to communicate. I guess the keyboard will just ignore all the stuff the kindle sends to its serial port, but that is probably not for granted, though. Then you would need software on the kindle which allows you to grab input from the serial port and do its output to the e-ink screen.

All this comes across being very natural to an average "hacker" type of guy, who's just custom with taking her/his soldering iron and programming a few controllers (I think I'm almost there, I still don't like soldering, though, but I've learned a bit and I can help myself). "It's not so hard but it's not so easy" is basically right, but by no means it is an easily approachable goal to the casual end-user type of guy. Some hackerish software mangling is involved, too.

That all said, I think geekmaster gave a very good answer. The serial port is most probably your best bet and the lowest hanging fruit around for this problem.

I have another suggestion, too: you could use some USB host device - like e.g. a broadband router featuring an USB port - and use this to plug both a USB keyboard and the Kindle into it and use it to forward USB keyboard input to the Kindle via USB networking (on the Kindle). That would be more for people like me that hate to get their hands dirty on hardware and tend to be happy with software hacking alone :-)

[geekmaster]

Originally Posted by hawhill

...
I guess the keyboard will just ignore all the stuff the kindle sends to its serial port, but that is probably not for granted, though.
...

The serial keyboards that I have (5 different models) do not even have the RxD pin connected. They are "send-only".

Regarding a link for a kindle 3 serial connector, look here (with photos):
https://www.mobileread.com/forums/showthread.php?t=99177
Because the connector is made from such a simple circuit board, I would not bother etching it. I would isolate the traces by cutting and peeling thin strips of copper from between the traces, with a sharp hobby knife (such as an X-Acto knife).

Regarding "not so hard but not so easy", the most difficult part is locating the documentation you need so that you can "RTFM", and there is FAR more RTFM than there is "rocket science". You must read, read, and read some more. I own over 10,000 physical books (mostly technical in many disciplines, including history, medicine, and law, plus some science fiction -- but mostly computer and electronics books) [an awful lot of dead trees], and I have read most of them. And reading is just the start. You really need "hands on" experience to truly learn this stuff in a way that makes it accessible longer than needed to just pass a test and then forget it. You must experiment and MAKE stuff (lots of stuff), and you must not give up, but keep at it until you succeed. That pretty much sums up the whole learning experience. You can do it if you want to. People can do far more than they believe, if they just get started and keep at it and finish what they start.

Regarding using a "USB host device", you can use a USB hub to connect multiple USB devices into a single USB host port. The device drivers need to know how to traverse the USB hub chain. The USB spec says that USB device drivers should scan up to 127 levels deep (how many hubs can be daisy-chained between host and device), but I have rarely seen software that looks more than two levels deep before deciding that its device is not attached.

The main reason I can see for daisy-chaining hubs is to get more distance. Each USB cable cannot be more than 16 feet long (about 5 meters). In theory, you could put up to 127 hubs between the host and device, each 16 feet apart from one another, giving a total distance greater than 1 kilometer (however, the spec also says the total distance should not be greater than 80 feet, due to timing constraints). Of course, these days it may be more appropriate to use USB-over-IP to extend USB over a long network cable (or even across the internet).

For people who hate soldering, you can use conductive paint instead. That works especially well for attaching small wires to kapton flex cables and flex circuit boards (such as the one used in the kindles to connect to the eInk display). Attempting to solder to that would probably damage it. The cheapest easily available conductive paint I know of is sold at auto parts stores for repairing rear window defroster/defoggers. You can even make simple circuit boards with conductive paint.

Everybody has to decide how to invest their own time. In my case my deep knowledge of many technical things has come at the expense of ignoring world events, sports, daily news, clocks and calendars, and other mundane things such as paying bills even when there is plenty of money. Although most information is free, it takes considerable time and effort to cram it all into your head, and comes at the expense of sacrificing time for other things. The first thing most hackers SHOULD sacrifice is their TV watching. Use that time to MAKE stuff! At least that is MY opinion on this subject. To each his own, as they say.

P.S. Please excuse my typing errors and occasional factual mistakes. My typing accuracy AND my knowledge recall accuracy are both degrading with age. I am an old-timer, at least by internet standards.

P.P.S. Here is a nifty little hack somebody could do to add sound output to the Kindle 4 (no speakers or headphone jack) without opening the case:
https://www.mobileread.com/forums/sho...8&postcount=29

[vdp]

Originally Posted by hawhill

...

I have another suggestion, too: you could use some USB host device - like e.g. a broadband router featuring an USB port - and use this to plug both a USB keyboard and the Kindle into it and use it to forward USB keyboard input to the Kindle via USB networking (on the Kindle). That would be more for people like me that hate to get their hands dirty on hardware and tend to be happy with software hacking alone :-)

Or if it fits your usage scenario you can do something similar over TCP/IP. For example you can use other device - PC/tablet/smartphone with support for USB/bluetooth keyboad - and just forward the keyboard events to Kindle. Only a very simple piece of software would be required in this case. If I am not mistaken, launchpad can be configured to listen for this kind of events over UDP and simulate key presses.

[RV987789]

@ geekmaster
Many thanks for the post and for their selfless teaching.
Regarding the use of time, as you say, sometimes you have to choose to leave certain things to make others.
I always liked the "hacker spirit" or the "do it yourself", mainly due to the products they sell are not always adequate to the real needs of users.
Unfortunately, I can give my time to expand my knowledge and gain experience in the field of electronics and not even to software development. I am essentially a "consumer and editor" of content (text) and what I need is a suitable tool for that use. The Kindle is great for reading but I also need to insert and edit text without damage to the eye.
So I'm looking for experienced people to orient me about some output that could be used by an average user like me (if it exists, of course).

@ hawhill
@ vdp
these solutions are really attractive!

vdp says:
"Only a very simple piece of software would be required in this case."

that's really souns great!

vdp says:
"If I am not mistaken, launchpad can be configured to listen for this kind of events over UDP and simulate key presses."

If it is so, maybe the solution it's so close, isn't?


Sorry for my English, I am Spanish speaking and "translate" my post into English using a dictionary

[multiprose]

Originally Posted by geekmaster

Although most information is free, it takes considerable time and effort to cram it all into your head, and comes at the expense of sacrificing time for other things. The first thing most hackers SHOULD sacrifice is their TV watching. Use that time to MAKE stuff! At least that is MY opinion on this subject. To each his own, as they say.

P.S. Please excuse my typing errors and occasional factual mistakes. My typing accuracy AND my knowledge recall accuracy are both degrading with age. I am an old-timer, at least by internet standards.

P.P.S. Here is a nifty little hack somebody could do to add sound output to the Kindle 4 (no speakers or headphone jack) without opening the case:
https://www.mobileread.com/forums/sho...8&postcount=29

hey geekmaster, if you aren't already, you might be interested in spaced repetition to strengthen memory and increase the efficiency of learning. i use a program called anki. the program can sync flashcards online and you can use the kindle web browser to complete exercises.

[geekmaster]

Sorry, rather off topic, but I want to reply:

Originally Posted by multiprose

hey geekmaster, if you aren't already, you might be interested in spaced repetition to strengthen memory and increase the efficiency of learning. i use a program called anki. the program can sync flashcards online and you can use the kindle web browser to complete exercises.

Spaced repetition occurs naturally with a foreign book and a dual-language dictionary. When I read "Les Miserables" in the original French language, at first I had to look up almost every word in my French/English dictionary, but as my reading progressed, more and more words had been looked up so many times that I had to refer to the dictionary less and less often. By the end of the book, I rarely needed to use the dictionary any more.

With most other learning, I am more of a "hands on" kind of guy. I prefer to learn stuff at the deep reflexive kinesthetic muscle-memory level, but it typically takes about 10,000 repetitions to train your spinal cord to react before the sensory triggers even reach your brain. My sensory triggers consist mostly of gravity pulling on my body limbs creating feedback that extends my sense of self out into the space around me.

I map a lot of my mental processes into muscle memory space. At one job, I even kept my thoughts and ideas on thousands of little notes attached to the wall next to me (my memory wall). Muscle memory allowed me to accurately reach for any content even with my eyes closed. I moved the notes around in clusters as my mental map grew and refactored. My memory wall functioned very much like add-on extended memory and became very reflexive and natural for me. I have tried to recreate that experience in recent years with a wall of monitors in front of me. I have replaced my seven 25-inch 1920x1440 CRTs with seven LCD panels (mostly 2048x1152, with one 1920x1200). Unfortunately, after switching to Windows XP (needed for my paying work) running as a 32-bit VM running inside 64-bit linux, my video cards will only let me use 3 monitors, because the linux nvidia and radeon drivers fight and the radeon is running in framebuffer compatibility mode, which only supports one monitor on that dual-head video card (as far as I can get it to work without too many distractions form what I WANT to do with my time). [I really feel horribly cramped with all the layers of buried windows on only three monitors.]

Anyway, trying to artificially use spaced repetition for rote learning does not work well for me unless reinforced by real physical activity (like using a paper bound dictionary).

[No, I am NOT on drugs! This is really how I think all the time.]

[yifanlu]

Why all this talk about a serial port? Who wants to walk around with a half opened kindle all the time? If you have another Linux machine (laptop, android phone, etc) just write a script or something that take key input, transfer over ssh or something, and forward (and maybe translate) the input on the kindle.