Laptop with Raspberry Pi Inside Learns to Speak Battery

Early in November we took a look at a one of the best Raspberry Pi laptops we had ever seen, using the shell of a Sony VAIO. Laptops used to be hulking beasts, and that played into [Frank Adams’] hands as he got rid of the motherboard and had enough space to replace it with a Raspberry Pi and a few other support boards. This took advantage of the laptop’s screen, keyboard, LEDs, etc. But what’s a laptop without battery power? [Frank] hadn’t cracked that nut until now.

Inside of Sony VAIO laptop turned Raspberry Pi computer
VAIO battery and charging PCB seen to lower left

Adding battery power is trickier that it sounds, but [Frank] managed to get the Raspberry Pi to talk to the original Sony VAIO internal battery. His work on the project is shared, but this part of the story is best found starting on page 29 of his PDF project details.

Using the original battery is a good move since it’s designed to fit and has a charger ready to interface with the port on the laptop case. But these batteries have logic inside them, and there’s the rub. Communications use the 2-wire System Management Bus (SMBus) which is well documented. But the when trying to use the Pi’s I2C [Frank] couldn’t figure out to send a repeated start command.

He ended up writing his own C program that bit-bangs the communications he needed and now has the Pi speaking to the battery and listening to what it hears coming back. Reading through his description of this is fun since he includes his observations from a logic analyzer captures. He suspects an occasional bad read is due to Linux interrupting code execution. He watches for and catches these bad reads in software and can now reliably read all the battery vitals.

The hack leaves him with a system that functions in much the same way the original computer did: plug it in and it charges. He did add some hardware that lets him take a voltage reading from the battery using an ADC on the Teensy that was already present to control the keyboard and case LEDs. This adds a small constant draw on the battery, but for now he doesn’t leave the battery connected when the laptop is not in use.

If you’d like to read our original coverage of this laptop, here it is.

The VAIO WIth A Pi Inside

Raspberry Pi laptops are not an uncommon sight, as many hardware enthusiasts have shoehorned the tiny board behind LCD panels into home-made cases.

[Frank Adams] has created one of the best Pi laptops we’ve ever seen, (for which we suggest you skip straight to the PDF). He’s removed the guts from an aged Sony VAIO laptop and replaced it with the fruity computer, alongside a Teensy to handle VAIO keyboard, buttons, and LED I/O via the Pi USB port. An M.NT68676 video board interfaces the VAIO display to the Pi HDMI, and a USB to SATA cable is connected to a 240Gb solid state hard drive. The laptop’s Wi-Fi antenna is routed to the Pi via a soldered on co-axial connector, and there is also a real-time clock board. There are a few rough edges such as a USB cable that could be brought inboard, but it’s otherwise well-integrated into the case. His write-up is a very comprehensive PDF, that should serve as a good primer to anyone else considering such a laptop conversion.

The result is a laptop that looks for all the world like a commercially produced machine, yet that is also a Raspberry Pi. In a strange way, a Sony laptop is an apt homecoming for the board from Cambridge, because other than red soldermask or very early Chinese-made models, all Raspberry Pi boards are made in a Sony factory in Wales. Whatever the donor laptop though, this is definitely a step above the run-of-the-mill Pi laptops. To see its competition, take a look at this very ugly machine with a bare LCD panel, or this laser-cut sandwich laptop.

Sandwich Together a Raspberry Pi Laptop

Ever since the Raspberry Pi was released to an eager public just over five years ago there is one project that seems to have been tackled more frequently than any other using the small computer from Cambridge: that of making a laptop with Pi for brains. Perhaps you feel you have had your fill of Pi laptops both good and bad, but it’s still a project that can bring up some surprises.

Does [Eben] carry a silver marker with him, laptops for the signing of?
Does [Eben] carry a silver marker with him at all times, laptops for the signing of?
[Archie Roques] is a young maker from Norwich, UK, and at the Raspberry Pi birthday party in early March he had rather an unusual laptop. He’d done the usual thing of mating the official Pi screen, a bluetooth keyboard/touchpad, Pi, and battery, but as always it’s the detail that matters. His case is a carefully designed sandwich of laser-cut plastic that somehow manages the impossible task of containing all the laptop internals while not being too bulky.

For power he at first used a 4 AH LiPo cell from a dead tablet with a Pimoroni LiPo power board, but since he hit problems with the Pimoroni board supplying both screen and Pi he’s switched to an off-the-shelf power bank. Unusually this laptop also has built-in audio, using another Pimoroni product, their speaker pHAT.

Where this laptop has a flaw though is in the display hinges. He has plans for a beautifully made 3D printed hinge, but for now he’s using a piece of tape, which though functional does not add to the aesthetic. When we saw it in Cambridge the keyboard was fitting more snugly than it does in the photos on his write-up, so perhaps he’s fixed some of its issues. Despite the in-progress hinge it’s a very usable little Pi laptop, and though (Hint, [Archie]!) he hasn’t yet published the design files for it, we’re sure when he does we’ll see other people building the same machine. They won’t be quite as exclusive as [Archie]’s model though, while he was in Cambridge he managed to get it signed by [Eben Upton], founder of the Raspberry Pi Foundation and judge for the 2017 Hackaday Prize.

We recently showed you a Pi laptop build in a cigar box that was useful in its detailing of the various modules required, but in the past we’ve shown you another one using the official touch screen, a lovely one in the style of a Psion palmtop, and vertically bulky yet small-footprint one, and another that keeps its presence hidden.

A tip of the hat to Norwich Hackspace.

Cigar Box Opens to Raspberry Pi Laptop

If you were to go back to the middle years of the twentieth century and talk to electronic constructors, you would find a significant number had a cigar box radio among their projects. Cigar boxes were fairly robust, readily available, and could easily accommodate the parts required to make a crystal set or a simple one-tube regenerative receiver. These days there isn’t much attraction to a simple AM radio though, so while they can still be fun to build, the cigar box radio only occupies a niche in vintage radio circles.

Cigar boxes, however, remain. [Mike] found a very nice antique cigar box, and made something unexpected, he put a Raspberry Pi in it and made something close to a laptop. Into the lid goes an LCD screen secured with wooden blocks, while in the body of the box goes the LCD controller, Pi 3, and battery charger and PSU modules. There are two sets of cells, one each for screen and Pi.

We like the idea and we like his write-up for its clear run-down of the modules required even though it’s mostly a plug-together build. We described it as “Something close to a laptop” because it has one glaring omission. He’s using an external keyboard rather than having incorporated one within the case. We think there looks as though there is plenty of room for one, so perhaps he’ll return to the project and upgrade it in that way. For reminding us that cigar boxes can make excellent laptop cases though, we’re thankful.

We’ve featured numbers of Raspberry Pi laptops over the years since the little computer’s launch. Just a small selection are this one using the official touch screen, a rather beautiful one in the style of a Psion palmtop, and one that is rather chunky but has a small footprint. Meanwhile in cigar boxes, we’ve brought you an excellent little 555 organ.

Raspberry Pi Laptop Uses The Official Touchscreen

We’ve seen a variety of home-made laptops using the Raspberry Pi and other single board computers over the years. Usually, they combine off-the-shelf USB keyboards and trackpads with HDMI monitor panels, and cases made from layered laser cut sheet, or 3D printed plastic.

[Surferboy]’s Raspberry Pi laptop is the latest effort to come before us, and its claim to fame is the use of the official Raspberry Pi 7″ touchscreen as a display. Full instructions and 3D printer files are available on Thingiverse so you can have a go at replicating it if a portable Pi is your thing.

He’s taken the bold step of not attempting to place all the Pi’s interfaces next to the outside of the case. Instead, he’s desoldered the Ethernet and USB ports. The USB connections were wired directly to the keyboard, display, and a couple of external ports on the right-hand side of his case. This leaves the finished laptop with no Ethernet. However, losing ethernet is a worthy tradeoff for the thinner package.

[Surferboy] also brought the GPIO header to a female socket on the rear of the unit. It’s unclear exactly what battery he uses except for a reference to the battery from his keyboard. Since a keyboard battery will be too small for Pi and display we are guessing a larger pack will be necessary.

Though the Ethernet port and battery issue would probably be a dealbreaker here this has the makings of a useful and compact laptop, it will be interesting to see if it is picked up and refined by the community.

Quite a few early Pi laptops used the Motorola Lapdock, a mobile-phone-into-netbook peripheral. Some others we’ve featured have been a bit chunky, but sometimes they can be objects of beauty.

Via Recantha.co.uk.