Apple Pi (Raspberry Pi in a Titanium PowerBook G4 case) build

[sesselpupser]

Hi guys,

So as I mentioned in the 'What have you done today' thread, I'm working on... Well, it's in the title.

I got the Pi for Christmas, it's the Model B 512MB version. I've struggled to work out what to use it for but I've settled on making a laptop out of it, or rather a portable computer, but I'll get to that in a minute.

I have a 2002 Titanium PowerBook G4 DVI sitting on my shelf, well, I did until I ripped it to pieces at least. It was missing the display inverter and several ribbon cables which would be difficult to replace so I figured it was as good as dead anyway, so I don't feel too bad about irreparably dismantling it...

Stuff that needs doing:
- The LCD needs a controller board. These are cheap and easy to find, however the make and model of the LCD in the laptop isn't, the information is hard to find on the internet and dismantling the lid to have a look on the off-chance it's written on the panel itself is too risky as it's epoxied shut and the titanium is extremely thin and fragile. This is the best list I can find so far:

Samsung PN LTN152W3-L01, LTN152W4-L01, LTN152W5-L01
AU Optronics Corp B152EW01

Lower resolution from pre-DVI models:
Samsung PNs LTN152W1-L01, LTN152W2-L01
AU Optics Corporation - PN B152W01
LG/Philips PN LP152W1

I've (accidentally) ordered a VGA controller board to suit an AUO B152EW01 but asked to change my order to a DVI board... We'll see what happens as that was about 12 hours ago and they haven't gotten back to me, but they are in Hong Kong so who knows.

- The keyboard needs an interface. The keyboard in the PowerBook is a tiny removable unit, I'm sure you know the type, with a ribbon connector which has roughly 30 or so connections, so I'm obviously convinced it's just a matrix. Then I remembered the Arduino Leonardo can be made to function as a keyboard, so I figure I should be able to use it to interface the matrix with the Pi... Maybe. I need to get the connector off of the motherboard first.

- The trackpad also needs an interface. It uses a Synaptics T1004 which, from what I gather, is a PS/2 device which would make sense I suppose. I ran into the biggest problem with that, though; I was going to hook it up to an Arduino running a PS/2 mouse program to see if I could get some sense out of it, but realised the ribbon is, well, a ribbon and therefore not exactly solderable, but the connector is nearly impossible to desolder without a hot air rework station, which I do not have. I ruined the two others of the same size in my attempts to remove them with my iron, then attempted to use single cores of multi-core wire to rebuild them... It didn't end well. Anyway, I'll just find a hot air gun, get an appropriate SMD breakout board (I guess) and get to it. Alternatively I'll solder directly to the trackpad and do away with the ribbon altogether.

- Fit a custom power connector. Apple's proprietary connector is no good; I don't have the original PSU any more and even if I did it only runs at one voltage; I will need 4 amps of 12V and probably about the same of 5V in order to run the Pi, Arduino(s, possibly), trackpad, USB hubs, WiFi dongle, etc, etc. So I'm thinking I might use a single barrel jack, give it a lot more voltage than I probably need and use on-board regulators to break it up into 5V and 12V... But at 4A each that's going to generate a fair bit of heat. I need to think about it, obviously.

After all that is sorted I should have a usable portable computer.


Then there's the fun stuff. I have plans for a lot of small details, ranging from a POST chime (even though there's absolutely no POST going on) to an emergency power capacitor so the Pi has time to save and log out if the power is cut.


But yeah, first things first:
I'll get LCD control board sorted first of all, but whilst I'm waiting for it to arrive I'm going to visit the London Hackspace (I just became a member yesterday) with the PowerBook logic board in hand to desolder the trackpad and keyboard connectors so I can get started on turning them into useful devices. Oh and I need to order a Leonardo, or at least look into how to flash a normal Uno (or DIY Uno-alike) to work the same way.

Also if I can't find the right LCD controller my plan is to turn the bottom half of the laptop into a case for the Pi anyway so I don't have to carry it, a keyboard, mouse and all the rest of it around all the time.

TL, DR: This probably isn't going to work, but I thought a few of you might be interested anyway.

 

[NissanSkylineN1]

I'm excited to see how this goes out.

 

[Robin]

I was going to do something similar soon. Raspberry Pi in a laptop case but the only two major issues are the battery power and the LVDS screen connection.

I know those ebay sellers who sell DVI or VGA to LVDS converters like the one you have ordered but would they have ones compatible for screens from like 12 year old laptops? Also how would you power the display?

Would be cool to see how this turns out however far you get, do post some pics 👍

 

[E28]

Interesting, I've been toying with the idea of getting a Pi. I've seen loads of Lego cases built for it, but this is certainly more original. 👍

Shame you had to take an old PowerBook apart, but I guess using it for something interesting is better than leaving it dead and sat around.

 

[sesselpupser]

I'm excited to see how this goes out.

Thanks, so am I!

I was going to do something similar soon. Raspberry Pi in a laptop case but the only two major issues are the battery power and the LVDS screen connection.

I know those ebay sellers who sell DVI or VGA to LVDS converters like the one you have ordered but would they have ones compatible for screens from like 12 year old laptops? Also how would you power the display?

Would be cool to see how this turns out however far you get, do post some pics 👍

1. Battery power is indeed an issue which is why I'm completely ignoring it by designing it to be a portable desktop instead of a laptop... It's a cop-out but as I said in the OP, batteries are a pain in the arse.

2. It depends on the display. The seller I ordered from included a partial list of panels, but they ask you to specify your panel when you order. You can also ask them if they can program the board for your panel before you buy. I think the boards are all the same, it's just the programming that changes, so who knows? You power the display with an external 12V 4A PSU, the controller board also comes with an inverter for the backlight. It's all taken care of by the DIY kit (I hope!).

3. Done and done.

Interesting, I've been toying with the idea of getting a Pi. I've seen loads of Lego cases built for it, but this is certainly more original. 👍

Shame you had to take an old PowerBook apart, but I guess using it for something interesting is better than leaving it dead and sat around.

The Pi is a great little thing but I don't think it has reached its full potential yet. Then again I've used mine for all of about half an hour. There's no Office-like suite (OpenOffice and LibreOffice haven't been ported, not yet anyway) so it's not great in that regard, but really I just want to be able to type notes and program microcontrollers and play with other electronics type stuff with it while I'm away from home.

And yeah, I felt bad at first but it's for a good cause, even if the cause turns out to be to prove that it can't be done (easily by an idiot). If it works out though I might have to gut the G3 I've got and use that as a fixed benchtop computer, as it is I have to keep walking to and from my Mac to read datasheets and such which is getting annoying.


Aaanyway, here's some photos of the gutted PowerBook. Photos taken with an iPhone so the exposure is a bit wonky at times, apologies for that. There's also a bonus shot of the manufacturing fault on my Pi (at least I assume it's accidental):

The ludicrously tiny trackpad connector (J28):

The internal support structure and heatsinks:

Annoyingly, the heatsink features a lot of anchor points for the case screws so for rigidity I think the majority of it has to remain, otherwise the bottom half of the case may be too flexible and therefore fragile. Likewise with the support structure, but that's less intrusive. I guess I have to wait and see, I may be able to get a replacement support structure made up out of a single piece of acrylic (I have access to a laser cutter now) so it might not be fatal if I have to bin the lot, it'll just be a big hassle.

Also, check this out. This is the Ethernet connector on my Pi. It took me a while to realise why it's raked like that.

You can just about see the last pin on the connector in the photo, it's bent into a V-shape so it doesn't actually go into the hole and you can see if you turn the board over that the lead doesn't go through to the other side! Weirdly (I say that with no knowledge of how Ethernet works, maybe that particular pin isn't used at lower speeds) it does still work. As I think I mentioned, though, I intend to desolder that connector, the USB connector and the yellow Composite connector in favour of off-board connectors with lower profiles, so instead of an over-under twin USB port I'll use side by side ports and for the Ethernet I might even try to get an SMD one instead. I don't need the Composite port, I don't think I need to remove it either though but it will help keep the size down which I think will be crucial, I have no idea how big the LCD controller and inverter boards are after all. Knowing my luck they'll have nice huge caps on them.

 

[Grayfox]

You need all pins on an ethernet.

See if you can put it into the hole and solder it otherwise RMA time.

 

[sesselpupser]

You need all pins on an ethernet.

See if you can put it into the hole and solder it otherwise RMA time.

It works as it is, but I'm going to remove and replace that connector anyway because it's too tall. Thanks for the info, I sort of assumed that the number of pairs used depended on the Ethernet speed so there was a chance it's not fast enough to use all of the pairs, and just by luck that pin belonged to one of the pairs not being used.

 

[Grayfox]

I take it you know how to desloder and solder?

 

[NissanSkylineN1]

I'd advise using a desoldering pump.

 

[Grayfox]

Solder suckers or Solder wick can work well if you know how to use them.

 

[Infinital-NG]

You only need 4 wires for Ethernet to work.

orange pair and green pair

looking at rj-45 jack tab down.

orange/stripe
orange
green/strip
open
open
green
open
open

That's for a cable though, but not sure on the jack.

If it helps any.

 

[Grayfox]

1 white and orange TX+
2 orange TX-
3 white and green RX+
4 NC *
5 NC *
6 green RX-
7 NC *
8 NC *

This applies to straight cables

 

[Robin]

How did you decide the AU Optronics panel was the one in your laptop? Did you just take a gamble?

I hate the way some screens are double sided taped to the bezel, as if 10 screws wasn't enough to hold it together! I couldn't get one open a while back either, after slightly lifting one corner the tape was so strong it started to bend the metal so I stopped.

 

[sesselpupser]

How did you decide the AU Optronics panel was the one in your laptop? Did you just take a gamble?

I hate the way some screens are double sided taped to the bezel, as if 10 screws wasn't enough to hold it together! I couldn't get one open a while back either, after slightly lifting one corner the tape was so strong it started to bend the metal so I stopped.

Pretty much took the gamble, but my research came up with that name more often than the alternatives. I'm kind of assuming that because the panels are interchangeable, even previous generation lower resolution panels work with it, then no matter what the panel is it should work if the controller I get is compatible with one of the interchangeable ones. But that's a gamble. It's not hugely expensive though (£20) so I'm happy to risk it. Once.

And yeah, tell me about it. The lid of this particular PowerBook isn't just screwed and taped together, it's epoxied too, hence why I haven't pulled it apart yet. I'm only doing that if I absolutely have to... Knowing my luck I'm going to have to of course.


Edit: And yeah, I know how to solder and desolder, though obviously I'm more familiar with the former than the latter (as I'm studying electronic engineering, not repair!). I think braid is the better option but I also think I'd be lucky to get it off cleanly, in my experience braid doesn't always get it all.

 

[sesselpupser]

Gah, the people I'm ordering the LCD controller from need me to open up the lid and get photos of the LCD for them. I won't have the time to do that for a while.

 

[sesselpupser]

Well I managed to convince the seller to just send me the board without checking the panel, I pretty much promised to not seek a refund if it's wrong. It's a gamble but not as much of a gamble as prying the case open, so I can live with it... I bet they send a kit with a different cable though so I'll have to do some tiny soldering to make an LVDS connector breakout board or something. Or they'll just send me a DOA board because I won't complain. But then 'broken' and 'unsuitable' are different, so.

And tonight I'm going to order an Arduino Leonardo so I might be able to get on with making an interface for the keyboard. Then I have to pop round the local hackspace with the laptop motherboard to get the various connectors off with hot air...

 

[sesselpupser]

Still making baby steps here, but I got the Leonardo today and confirmed that the Pi requires no additional work to get it to recognise it as a keyboard. I say 'confirm'; I got it to type 'uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu' at the login prompt, so that's something. Now I have to work out how to get the whole keyboard matrix to interface with the Leonardo in a latency-free fashion, which will be interesting.

 

[sesselpupser]

Last post until I have some photos to share:

I've been desoldering both PTH and SMD components since I last posted, the former with desolder braid and the latter... Well, let's just say I haven't been doing it to harvest parts, I just want to clear the areas around the keyboard and trackpad connectors on the donor board so I can get a closer look at them. Of course that hasn't amounted to much because the board is more than just double sided and I don't have an X-ray machine so following the tracks is somewhat difficult, but at least I can get my iron around the connectors I want to remove so when the Chip Quik kit I ordered arrives I'll be able to desolder them quickly, which hopefully means the plastic parts won't warp, burn or melt, which is obviously essential.

So the short-term plan is:

Display:
- Get LVDS board
- Pray LVDS board works, if not then crack the lid open and order a new one when the LCD is confirmed, if the LCD or lid is damaged in the process then just bin it entirely and focus on making a portable computer with integrated keyboard, trackpad, HDMI and DVI.
- Make custom tiny, tiny HDMI > DVI cable.

Keyboard and trackpad:
- Desolder ribbon cable connectors from PowerBook donor board
- Design, print and manufacture adaptor PCBs to make life easier
- Work out whether or not the trackpad really is PS/2, if it is, get a PS/2 > USB adaptor, if it's not see if it can be made to interface with an Arduino... If it can't, forget about it and find a small but comfortable mouse instead.
- Find a custom Arduino Leonardo keyboard project on the internet, 'borrow' the code and make it work. If this doesn't work out just scrap the whole idea.


So basically I can live without an integrated display and pointing device, but without the built-in keyboard having the Pi in a 15" laptop case becomes a bit pointless so I'd just scrap the idea completely. Naturally that means that's the one part I'm really keen to get going on, but I can't do anything until I've wired up the connector in a manner I can test with. Once I have these three basics nailed down I can get started on the power supply and fun stuff like having an emergency battery for the Pi or my phone (or both), internal speakers, GPIO port, internal hard drive and so on. Hopefully there will be something to share in a week or two.

 

[bergauk]

I actually thought about this the other night.. how are you going to power the lcd? From what I understand of the Raspberry Pi(I've ordered one recently and have been scouring the internet for any sort of information on it).. They don't really supply much power themselves. They take 5v and however many amps(beyond the 700milliamps required) they need but beyond that.. they can't use any more voltage.. So I'm curious if you've thought about it at all.

 

[sesselpupser]

The LVDS board I ordered requires an external 12V PSU, so it powers itself. Speaking of which, the board has arrived but naturally the connector is the wrong size...

 

[sesselpupser]

Just a quick update:

I'm pretty much completely broke and have been for a little while so buying the 12V 4A PSU to fire up the LVDS board has been pretty low on my shopping list lately. I have, however, desoldered a lot of the motherboard of the laptop and then Stanley knifed the keyboard connector off so in my spare time I've been attempting to probe that, with limited success. I have, however, worked out that they appear to have gotten round the requirement for diodes (to stop keypad ghosting) by giving each key it's own resistance, therefore the inputs on the keyboard interface must have been ADCs to convert the analogue voltage into a different binary code depending on how many keys connected to that particular input are pressed. I think. I could buy a spare keyboard and pull all the keys off it to get to the membranes, but... That costs money. Then there's the problem of working this keyboard out as well, if I need an ADC per input (which seems likely) the price is going to shoot up! If that's what's needed I'm going to abandon the whole thing and look towards using a pre-made keyboard and trackpad (Apple make some nice examples of these) and laser cutting a case for them instead.

As for the trackpad, I've made no progress. Again, I need to buy a PS/2 - USB adaptor to test my theory, and if I'm wrong then that's just a waste of money. I want to work out the keyboard first as there's no sense in having a trackpad without a keyboard.

So yeah, the current tasks are just what I can do for free, which is the keyboard, and that's very, very slow going.

 

[sesselpupser]

Well the keyboard is almost finished! Coding, I mean. It looks like this right now:

So it's hardly compact yet, but it will be. I haven't coded the modifier keys and there's nothing to limit the key repeat rate, also the caps lock LED isn't wired in yet (nor is it coded). I also want to pretty much flip the entire code over, right now it works on high signals but for noise robustness it would be better if it worked on low signals. Still, it's all very exciting, it only really took about three days to code and two of those days were probably more Forza 4 than coding.

 

[sesselpupser]

Rather than finish off the keyboard I've moved on to the trackpad. I've done almost all I can without buying anything; I've made a pinout for the connector, researched the PS/2 protocol a little and found a PS/2 cable from an old, old mouse. All it should require now is for me to hack the connector off of the motherboard the same as I did with the keyboard, solder the relevant wires on and then hook it up to a PS/2 - USB converter.

The problem with that is, they're all bloody expensive or they're crap. Active converters seem to cost between £15 and £30, there are some for £5 but reviews say they're just passive adaptors, and it doesn't help that they all look identical in the pictures. I have actually ordered one, it was £14 after P&P, so I'm thinking I'll just cancel that order and buy another Leonardo instead; it can do more and is only £2-3 more expensive. If I remove the headers and barrel jack adaptor the Leo is super thin so space shouldn't be an issue, it may even fit underneath the keyboard.

This does mean putting together a proper parts order so that the P&P isn't wasted and I can't really think of anything else I need right now, so maybe I'll just buy a load of passives and miscellaneous stuff.


Edit: Bah, it doesn't look like the trackpad is going to work. I've wired it up according to this pinout:

And I'm running a PS/2 mouse example sketch on my Arduino (I've tried two of them to make sure), but nothing is happening; the serial monitor doesn't respond. So I'm guessing the controller IC is dead, which sucks. I've ordered a spare from Ebay for $11, but I wouldn't be able to actually replace the entire trackpad in my laptop with it because that would mean somehow peeling a metal plate which is glued to the titanium case off without damaging either the plate or the case, swapping the trackpads over then replacing it. If I can get the replacement to work using the same ribbon cable the plan is to work out how I can swap the T1004 chip over. I really can't see how I could do that with the equipment I have but maybe some ChipQuik and an industrial heat gun will do the job... Or maybe I'll find a replacement top case. Or an otherwise dead laptop. That would be ideal because then I could crack open the lid to get a look at the LCD without so much fear of ruining the one I want to keep.

 

[mp10]

Good to see you're making some progress, I see you're also using the Arduino to work with the keyboard, but I'm curious to see how you'll integrate it with the Raspberry Pi.

I did a small project back in college with the Arduino Duemilanove, it was nothing complex; had a few sensors attached to it was all. The pic of the keyboard and Arduino brought back some good memories, i remember the jumper cables we were supplied were terribly loose, kept falling out from the breadboard. Good luck 👍

 

[sesselpupser]

The Duemilanove was serial only, wasn't it? They've moved on a lot since then, from the Uno - which had a separate ATMega 8U2 to convert the USB data to serial - to the Leonardo I'm using now, which does the USB conversion in the main chip itself which, annoyingly, is a tiny SMD IC so I can't easily make my own like you can with the Uno.

Aaanyway, this is just a long, roundabout way of saying the Leonardo reads the keyboard and sends out USB keyboard HID commands directly, so it will work with any computer in the state it's in now (which is identical to what it was in that photo). I've already tested it on my Mac, it needs work but you can type legibly with it.


Annoyed about the trackpad though. Hopefully this spare I ordered will help confirm whether or not the IC on the trackpad I have is dead, I figure if the new one doesn't work then it's something I'm doing wrong with the wiring. There are three connections on the motherboard connector that I haven't touched, as far as I can tell one is common with the ground anyway so I shouldn't need to do anything with it and the other two don't even go as far as the trackpad itself... It's weird. It's too late to think about that right now though.

Good luck 👍

Thanks!

 

[mp10]

Yep that's right the duemilanove was serial, i think so was the ATmega328. I've still got it lying around somewhere, might check it out, see if i've got my old data on there.

 

[sesselpupser]

Yeah so it's looking pretty certain the trackpad isn't going to work. I got the spare yesterday and just soldered it up today, it should work but doesn't, so either they're both dead or there's a trick to them I'm not getting. I can't do any investigation without an oscilloscope but I don't want to spend any more time on it for now as I have college work to be getting on with, but it's definitely not the Arduino because it works fine with a PS/2 mouse so it must be the trackpad.

I have however found a wireless Mighty Mouse (you know, the ones with the trackball that works once and then never again?) so I guess that'll do for now, that is if it still works; the batteries had leaked so badly inside it that it took a while to pry the battery cover off (as acid had crystallised in the catch) and then even longer to get the batteries out... The contacts look terrible, as you'd expect, but some contact cleaner or something should sort that out.

Then I just have to spend £15 on a PSU for the LVDS board and I get to worry about getting the LCD working instead. Woo.

But the important thing is the keyboard works, if all else fails I can at least package the Pi with an integrated keyboard, USB hub and a display connector. Having to carry it all separately is the main reason I've barely used my Pi. Because I'm lazy.

 

[mp10]

I had a quick look around on a website i used to use, Instructables, and I've found this but not sure if it will help you out.

http://www.instructables.com/id/Arduino-Laptop-Touchpad/

 

[sesselpupser]

Thanks, I'll take a look at it ASAP but for now I'll have to sleep on it. The thing that concerns me most is that a PS/2 mouse works fine but the trackpad doesn't, even though I'm certain it's wired up properly. I saw a Synaptics technical document which had 10k pull ups on the clock and data so I tried that too and it still didn't work. I think it's an oscilloscope job but predictably I don't have one!

 

[matrox]

Hey,
I'm getting a Powerbook g4 and I'd really love to join this project.
At the end of the month I'll be able to buy the parts.
I'm really new to this (Well I'm studying IT but we didn't do hardware projects till now) so it would be great if you could Help me getting as far as you got