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Re: Build a laptop reusing a dead one.

Posted: Mon Aug 22, 2011 9:04 pm
by diggy
If there was a way to connect Rpi to lcd screens (see LVDS post) it would kick butt to rip the internals of any old laptop and put an Rpi, connect the keyboard and touchpad (usually both usb internally), stuff an extra array of batteries in the free space and have a laptop that can run continuously for a couple of days on batteries!!!

I have a dead laptop at hand.
Waiting for Rpi to launc.
If only we could attach LVDS screens.... :(

Re: Build a laptop reusing a dead one.

Posted: Mon Aug 22, 2011 9:28 pm
by RITRedbeard
I'm working on a circuit (or exploring ICs) that together will probably cost the same amount or less as Raspberry Pi (less if you can sample) that will work to interface the TMDS protocol HDMI uses and ships it to LVDS.

Don't throw away your dead laptops yet, folks.

Re: Build a laptop reusing a dead one.

Posted: Mon Aug 22, 2011 9:47 pm
by diggy
Quote from RITRedbeard on August 22, 2011, 22:28
I'm working on a circuit (or exploring ICs) that together will probably cost the same amount or less as Raspberry Pi (less if you can sample) that will work to interface the TMDS protocol HDMI uses and ships it to LVDS.

Don't throw away your dead laptops yet, folks.



I can't wait! That could give Rpi another extra usability boost!!

Think carputers, car entertainment centers, info kiosks, you name it!!

Re: Build a laptop reusing a dead one.

Posted: Mon Aug 22, 2011 9:59 pm
by obarthelemy
that would be wonderful !

Re: Build a laptop reusing a dead one.

Posted: Wed Aug 24, 2011 6:04 pm
by RITRedbeard
Update: Samples are sent to my uni address, they should arrive sometime today, I'll be arriving there on the Aug 29th-30th.

The hard part will be creating the circuit and soldering (these are in pretty small packages) and I've never done SMD work before, so it will take some time (learning, getting parts, research, etc).

This is by no means impossible and I wouldn't be surprised if someone beat me to the punch in the mean time. Raspberry Pi is not only a good means of formal technological education but also useful in the realm of sustainability. In the context of reducing electronic waste and also using lower power devices.

Re: Build a laptop reusing a dead one.

Posted: Thu Aug 25, 2011 4:58 am
by RITRedbeard
So the plan is to feed the TDMS data from HDMI to TI's TFP401, then feed that data into TI's SN75LVDS83B. Theoretically, it should work. I recommend anyone with EE experience or SMD work to sample the chips and see if you can get it to work. I expect my first attempt to fail. Luckily, we have until November. :)

TFP401A is ~$9.88 depending on what package you get it in.
SN75LVDS83B is ~$7.88.
Roughly the cost of a Model A, but having such a powerful tiny computer in a laptop?
Priceless!

Spec Sheets:
http://www.ti.com/lit/ds/symli.....fp401a.pdf
http://www.ti.com/lit/ds/symli.....vds83b.pdf

Re: Build a laptop reusing a dead one.

Posted: Fri Aug 26, 2011 7:41 pm
by Chris
Quote from diggy on August 22, 2011, 22:47
Quote from RITRedbeard on August 22, 2011, 22:28
I'm working on a circuit (or exploring ICs) that together will probably cost the same amount or less as Raspberry Pi (less if you can sample) that will work to interface the TMDS protocol HDMI uses and ships it to LVDS.

Don't throw away your dead laptops yet, folks.



I can't wait! That could give Rpi another extra usability boost!!

Think carputers, car entertainment centers, info kiosks, you name it!!
I have been thinking car computer from day one

Re: Build a laptop reusing a dead one.

Posted: Tue Sep 13, 2011 2:22 pm
by abishur
@ RITRedbeard were you able to play with this any?

Re: Build a laptop reusing a dead one.

Posted: Tue Sep 13, 2011 4:47 pm
by Lakes
This would be fantastic if you can get it work.

Re: Build a laptop reusing a dead one.

Posted: Tue Sep 13, 2011 4:48 pm
by Josh
If it can be run off some AA batteries, I would love to see it running off a laptop one. It would last for days...

Re: Build a laptop reusing a dead one.

Posted: Tue Sep 13, 2011 4:49 pm
by Josh

I have been thinking car computer from day one
I'd love to see that!
At least there won't be any issues about your car catching fire :D since it uses a wattage of, ummm, nothing!

Re: Build a laptop reusing a dead one.

Posted: Wed Sep 14, 2011 3:32 pm
by Goggles2114
Color me interested. I mean buying a junker off ebay, preferrably something super OMFGOLD then reviving it.

Priceless.

Re: Build a laptop reusing a dead one.

Posted: Thu Sep 15, 2011 9:00 am
by thepanoguy
Take a look at:
http://repair4laptop.org/notebook.html

The site contains links to modded laptops and picture frame circuits.

Re: Build a laptop reusing a dead one.

Posted: Thu Sep 15, 2011 6:57 pm
by Goggles2114
Handy link is Handy.
+1 to you.

Re: Build a laptop reusing a dead one.

Posted: Fri Sep 16, 2011 10:11 pm
by Andius
The problem I see is not using the laptop battery but charging it up.

Re: Build a laptop reusing a dead one.

Posted: Sat Sep 17, 2011 9:18 am
by tufty
If you're after an HDMI - LVDS bridge, they are available off the shelf for various LCD panels. http://stores.ebay.com/njytouch stock various relatively cheap controller boards that will do DVI to LVDS so all you need is to hook up HDMI to DVI.

Re: Build a laptop reusing a dead one.

Posted: Sat Sep 17, 2011 7:01 pm
by abishur
I've seen those boards, $30 is a nice enough solution, but I was hoping for a more DIY solution for less cost than the r-pi itself ;)

Re: Build a laptop reusing a dead one.

Posted: Wed Sep 21, 2011 9:27 am
by Skygod
LVDS onboard would definately be a nice touch, but getting cables fabricated seems to make the proposition financially unviable.

I've got a few working screens from recent Acer laptops that have died (mainly due to owners carelessness) and they use LVDS connector and no requirement for invertors.

Using the Raspberry Pi with one of these screens and USB HDD / KB / Mouse would make a nice portable HTPC (or Karaoke player here in Thailand) which could then be hooked up via HDMI when at home.

Even an extra $10 - $15 for the connector as an add-on would make this project feasible.

Re: Build a laptop reusing a dead one.

Posted: Wed Sep 21, 2011 9:32 am
by stuporhero
Skygod - I used to have an Acer laptop. Ripped that screen right out and put a full HD in it - fantastic! Bought it from some place in West London I think...

Re: Build a laptop reusing a dead one.

Posted: Wed Sep 21, 2011 9:38 am
by RITRedbeard
Update: Classes are kicking my butt. Been a bit under the weather lately.

Still have the chips. I think I am going to design the circuit up in Eagle, have my EE buddies look it over, order the one or two last remaining parts I need and then have Sparkfun design the PCB for me.

An off-the-shelf ebay solution might work but the DIY solution will definitely have a smaller footprint if you care about that sort of thing. I do, since I'm going to be stuffing Raspberry Pi back into laptop guts, thus the experiment. If I can save in batch maybe I can send Eben and company one of the LVDS dongles or other people so they can test what panels work well and what ones don't work well, etc... and how it affects HDMI audio. (Sure there is a way to route that signal out with a special cable mod, though... maybe not if depends on clock)

Sorry! Not an electrical engineer, just a software boy. Still workin' on it.

Re: Build a laptop reusing a dead one.

Posted: Sat Oct 01, 2011 7:08 am
by RITRedbeard
Quote from abishur on September 13, 2011, 15:22
@ RITRedbeard were you able to play with this any?

Unfortunately my classwork is keeping me busy. If these chips weren't in such ridiculous packages and I could work Eagle, I might be able to get PCB ordered from BatchPCB.

Reference:
http://e2e.ti.com/support/inte.....21993.aspx TI Guys talking about the LVDS transmitter chip(s).

http://bb-lvds.blogspot.com/#e.....ct=3592974 Beagleboard LVDS using same transmitter chip

DS90C387A from National Semiconductor will work for shipping off the LVDS as well.
The DVI/HDMI decode is in a 100HTQFP package, though.

Also 1.8VDC regulator if you want to use the sn75lvds83b

DVI decode can be skipped if we can get access to TTL differential pairs from the GPU, similar to the Beagleboard.

Re: Build a laptop reusing a dead one.

Posted: Sun Oct 02, 2011 12:06 pm
by crispy
Its nice to know someone is working on this. I have no electrical engineering skills whatsoever, but can follow instructions on soldering what parts together quite easily :)

I have also made a thread like this: http://www.raspberrypi.org/?pa.....#038;t=621

No replies though, and we might as well continue here.

I took my Eee pc apart a couple of days ago to see what might cause trouble in this project. The LVDS should easily be doable as you've shown, but the connector from the keyboard and the mouse seem very odd -- not just 4 pins that would make it look like a USB device to my untrained eye, but like 10 for the keyboard and 6 or so for the trackpad. Another concern is hooking up the battery to the rest of the system. Things like charging, connecting battery as a device to be monitored by the OS. A last thing would be to build in a small USB hub.

Re: Build a laptop reusing a dead one.

Posted: Sun Oct 09, 2011 3:55 pm
by Wes1180
Would be nice if the case where the keyboard is was transparent, to show the raspberry pi, get a sticker with the logo to go over the existing branding etc.

I would like to do this, i've seen some sort of cheap broken laptops on ebay by searching "laptop faulty", if anyone knows where you might be able to pick them up from other than here, that'd be cool

Re: Build a laptop reusing a dead one.

Posted: Sun Oct 09, 2011 4:12 pm
by Thunder__X
Quote from crispy on October 2, 2011, 13:06
Its nice to know someone is working on this. I have no electrical engineering skills whatsoever, but can follow instructions on soldering what parts together quite easily :)

I have also made a thread like this: http://www.raspberrypi.org/?pa.....#038;t=621

No replies though, and we might as well continue here.

I took my Eee pc apart a couple of days ago to see what might cause trouble in this project. The LVDS should easily be doable as you've shown, but the connector from the keyboard and the mouse seem very odd -- not just 4 pins that would make it look like a USB device to my untrained eye, but like 10 for the keyboard and 6 or so for the trackpad. Another concern is hooking up the battery to the rest of the system. Things like charging, connecting battery as a device to be monitored by the OS. A last thing would be to build in a small USB hub.

Synaptic touchpads are usually ps/2 and macbook track pads can be converted to usb.

Re: Build a laptop reusing a dead one.

Posted: Tue Oct 18, 2011 6:41 pm
by jewesque
I have an older Dell laptop (I forget the model) that I'm more than happy to sacrifice in the name of getting this project rolling.