AVRphone is a barebones touchscreen cellphone

This little device is a prototype cellphone based on the ATmega128 microcontroller (translated). It boasts a 2.4″ touchscreen display which serves as the keypad, and uses the SIM100S module which takes care of the GSM radio communications. But the hardware isn’t the only attractive part. Judging from the screen shots a fair amount of time went into building the user interface too.

We seem to have a bounty of cellphone builds recently. This one is quite clean, and boasts a smaller footprint, and larger screen than this barebones example. There is a white paper available if you’re interested in digging a little deeper than the overview post. But it’s written in Czech and we didn’t see a way to provide a machine translation other than copying the text from the PDF file and pasting it into a translator.

µPhone is small and home made

[Victor] popped up in the comments of yesterday’s DIy Cellphone to show off his own home made phone, the µPhone (google translated). [Victor] has put some effort into making this thing very compact. As you can see in the video after the break, he even left off the number pad to save space. Instead, you do everything by using a small joystick and two buttons. He claims that he really only calls a small number of people, so this layout works fine once he has programmed their contact information in.

For some reason none of the pictures are showing up in the extensive forum thread on the project. It is fun though, to follow along as he tries to get this thing working.

[Read more…]

DIY cellphone

Here’s an interesting concept. Lets make a kit to build your own super simple cell phone. Thats basically what a group at the MIT media lab is proposing with this prototype. Consisting of an SM5100b GSM module and a 1.8″ 160×128 pixel LCD screen on a very basic board holding some buttons, this thing is pretty bare bones. Barely any features aside from sending/receiving calls. It does have caller ID though. At$150, it isn’t really that competitive compared to the phones you’d get from your provider, but it is just a prototype.

We particularly like the laser cut flex areas for the buttons on the front.

[Thanks Paul]

QArt codes, the better way to put picture in a QR code

[Russ Cox], current Googler and formerly of Bell Labs, posted an awesome guide to putting images in a QR code. Unlike this terrible attempt I wrote last August, [Russ]’s method does much more than simply paste an image into a QR code and hope the error correction passes. This new method generates a unique URL to be encoded for each QR code. In other words, the embedded image is actually part of the QR code and not just a copy and paste attempt.

The basis of [Russ]’ hack is the ability to change the message contained in a QR code to be made of either ASCII/UTF-8 or decimal numbers coded as binary. By appending an anchor tag (i.e. http://swtch.com/pjw/#123456789...) to the URL that will be encoded, [Russ] can change a whole bunch of pixels in a QR code to make just about any image.

With a few tricks like building new Reed-Solomon encoded blocks, [Russ] can change where in the pixels required by the QR code are placed. This allows for the full-width image of PJW’s binary likeness to be displayed in the QR code.

[Russ] put up a QArt coder that allows anyone to put a pixelated image in any QR code. [Luke Shumaker] (thanks for sending this in, [Luke]) took this tool and put the ‘ol skull ‘n wrenches inside a QR code pointing to hackaday.com. Very nice work from [Russ], and puts my work to shame. I’ll go cry in a corner now.

Poking at the femtocell hardware in an AT&T Microcell

Here’s a picture of the internals of an AT&T Microcell. This hardware extends the cellular network by acting as its own cell tower and connecting to the network via a broadband connection. So if you don’t get service in your home, you can get one of these and hook it up to your cable modem or DSL and poof, you’re cellphone works again. [C1de0x] decided to crack one open and see what secrets it holds.

On the board there are two System-0n-Chips, an FPGA, the radio chip, and a GPS module. There is some tamper detection circuitry which [C1de0x] got around, but he’s saving that info for a future post. In poking and prodding at the hardware he found the UART connections which let him tap into each of the SoCs which dump data as they boot. It’s running a Linux kernel with BusyBox and there are SSH and ROOT accounts which share the same password. About five days of automated cracking and the password was discovered.

But things really start to get interesting when he stumbles upon something he calls the “wizard”. It’s a backdoor which allow full access to the device. Now it looks like the developers must have missed something, because this is just sitting out there on the WAN waiting for someone to monkey with it. Responses are sent to a hard-coded IP address, but a bit of work with the iptables will fix that. Wondering what kind of mischief can be caused by this security flaw? Take a look at the Vodafone femtocell hacking to find out.

GSM modem means wireless serial connections

By now, most of us have seen have seen one of those GSM to wi-fi hotspot bridges. They’re interesting devices, and being able to carry a small wireless router with you at all times is very handy. Surprisingly, we haven’t seen many builds featuring these portable wireless hotspots, something probably due to the effort in breaking out a serial connection on these devices. The people at Open Electronics decided to build their own small serial-enabled cell phone modem, a boon to someone wanting a serial connection to any place with a cell tower.

The Open Electronics GSM/GPRS/GPS modem includes a header for an FTDI USB serial chip and a GSM module. Plug one into your computer and after a few short commands into a terminal, you’ve got a serial connection to nearly anywhere in the world.

The cost of the setup is a little high – around 80€ or $100 USD – and you probably should buy more than one so you can also receive data. While it is more expensive than the XBee wireless boards we see often, this GSM modem isn’t limited to the 300 foot range of the XBee. We’ll probably see this in a high altitude balloon before too long.