Soon…

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Soon…

Gaming with the guys.

Final Product.

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Final Product.

Firmware updating and hardware tweaking before Christmas (note the eggnog).

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Firmware updating and hardware tweaking before Christmas (note the eggnog).

The system up and running for testing and debugging without the screen attached.

To exhaust the hot air from the case, four holes were cut on the side to install four 40mm fans. After a few coats of paint, the assembly begins!

Since the Xbox 360 runs hot enough on it’s own with its jet-engine-esk fans, knowing the temperature of your Xbox Laptop is vital. That’s why i’m using dual ADT7410  temperature sensors. These sensors use the same  I²C interface as the LCD and potentiometer and due to their entirely integrated circuitry, do not require calibration. One will be mounted on the CPU and the other, on the GPU.

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Since the Xbox 360 runs hot enough on it’s own with its jet-engine-esk fans, knowing the temperature of your Xbox Laptop is vital. That’s why i’m using dual ADT7410  temperature sensors. These sensors use the same  I²C interface as the LCD and potentiometer and due to their entirely integrated circuitry, do not require calibration. One will be mounted on the CPU and the other, on the GPU.


I am using a digital potentiometer to control the volume of the amplifier over I²C. The DS1807+ is a 54K ohm digital potentiometer that was specifically designed for audio volume control. It can control two individual circuits (stereo) with 64 taps on each channel (including a mute position which provides even higher attenuation).

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I am using a digital potentiometer to control the volume of the amplifier over I²C. The DS1807+ is a 54K ohm digital potentiometer that was specifically designed for audio volume control. It can control two individual circuits (stereo) with 64 taps on each channel (including a mute position which provides even higher attenuation).

I’ve always wanted to try my hand at interfacing micro-controllers, so I ordered an Arduino Uno from RobotShop as well as a 4 Line LCD screen that communicates via I²C bus. The I²C interface is a two-wire system that has a data and a clock line. The clock line is pulsed every time a new bit is available on the data line (there’s quite a bit more to it than just that, but I’m not going to write an entire tutorial on how to use / program for an I²C interface). The Arduino will be the brains of the laptop, handling capacitive touch controls, temperature monitoring, volume control, fan speed control, video mode selection and console status.

Finally found time to put in a large order to Digi-Key

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Finally found time to put in a large order to Digi-Key

The monitor I chose is an Acer G185HV that I picked up at BestBuy for $100. It’s an 18.5”, 1366 x 768  LCD. The only reasons why I chose it were because of the size and price. It certainly isn’t the prettiest looking monitor but it’s good enough for on the go gaming. Almost all LCDs come in three main sections: the metal LCD frame which holds the LCD and back-light, the driver board and the power board. I used JB Weld to attach binding posts to the back of the metal LCD frame to hold the driver and power boards and then attached four “L” brackets to the sides of the frame to mount the entire assembly into the lid of the case. 9  wires had to be extended from the monitor which are: Neutral, Line and Ground for mains voltage, as well as R, G and B uncompressed video signals, Horizontal and Vertical Sync and video ground which are all part of the VGA signal. 

To create a DVD drive activity LED, I used the same little trick that I had thought up when wanting to do the same with an old Playstation 2 DVD drive. The BenQ drive found in this particular Xbox uses a 2 phase stepper motor to control the slide arm which holds the laser assembly. The stepper motor is driven via a R2S30201FP IC which is is able to control the spindle motor as well as 5 channels of actuator functions (drive open / close motor, laser focusing, etc…). For the slide stepper motor, it uses PWM (pulse width modulation) to control the voltage and chopper drive to control the current of each phase. Tying a resistor followed by an LED to one of the phases on the stepper motor will give us a crude indication of when the disc is being read.

Continuing the work on the power supply, 4 lines were required to run to the Xbox motherboard and 2 to the mains. The Xbox requires a 12 volt line (3x 18 gauge wires are used for load distribution), a neutral or negative line (again, 3x 18 gauge wires), a 5v standby line as well as a power enable pin that, when supplied with 5 volts (from the 5v stby line) activates the 12 volt rail. On the opposite side, we need the load and neutral lines to tie into the mains. There is still work to be done; namely adding the fan connections and possibly rerouting the LED connections. The 4 lines from the power supply will run to a terminal bus and then to the Xbox motherboard for easy disassembly of the system. The mains lines on the other hand, will pass through a panel mounted fast acting fuse as a safety precaution. 

I’ve also been busy working on the audio amplifier that will power both the headphones and internal speakers. I’m using a modified amplifier circuit based on the TDA2822M chip,which is a class AB stereo amplifier IC that can output 2 Watts at 16 ohms. I’ve replaced the power filtering capacitor with a larger one in order to prepare it to be used with the switching power supply (as apposed to the linear type it was designed for). I’ve also added a 3 pin header which is the beginning of the modular type system all the electronics parts i’m building will be part of. All of the connections on the board will be replaced by terminal blocks for easy disassembly of the system.

I’m no where near finished with the audio amp, but have got some good ideas as to how the amp will be controlled but all the goodies will have to wait until I can get a large order in to Digikey…

An old spring loaded flip open CD-ROM tray faceplate is going to be used as the DVD drive faceplate on the case. I used a plastic filler to fill in the holes and slots where the volume control and buttons used to be, sanded it down, gave  it a white primer and a metallic grey coat. I also installed the standard 3 pin power cord coupling which will get plugged in to power both the 360 and the screen.