English فارسی Suomi
Français Nederlands Translate

XO Users Manual (Rev 2011)

THE X0-1.75

"The XO-1.75 laptop is a refresh of the XO-1 and XO-1.5 laptops. In our continued effort to maintain a low price point, OLPC is again refreshing the hardware to take advantage of the latest component technologies. This design, while separate from the XO-3 tablet effort, uses the same very low power electrical design. It continues to use the same industrial design and batteries as XO-1. The design goal is to provide an overall update of the system within the same industrial design and external appearance. Overall, the target was to greatly improve the power consumption while reducing the purchase cost."

 

Hardware Specifications 

Physical dimensions

  • Approximate dimensions: 245 mm × 230 mm × 30.5 mm (see drawing to the right for detailed dimensions)
  • Approximate weight with LiFePO4 battery: 1.45 kg (~3.20 lbs);
  • Configuration: Convertible laptop with pivoting, reversible display; dirt- and moisture-resistant system enclosure; no fan.

 Core electronics

XO-1.75 is designed around the Armada 610 system on a chip.

  • CPU: Marvell Sheeva ARM (PJ4);
    • CPU clock speed: 800 MHz (superscalar and out-of-order instruction execution);
    • ARM instruction set compatible (including Thumb-2 and Wireless MMX2);
    • ARMv7 architecture compatible;
    • 32 KB L1 I-cache, 32 KB L1 D-cache, 256KB L2 cache;
  • The 610 includes hardware video encode/decode, a 3D graphics engine, display controller, USB, SDIO, and other system interface and management functions
  • DRAM memory: 512 MB DDR3 dynamic RAM;
  • Mass storage: 4 GiB NAND flash in an eMMC device soldered to the motherboard.
    • An internal full size SD card is provided for repair/replacement (not user-changeable without opening the unit with a screwdriver);
    • externally accessible full-size SD card slot;
    • No rotating media.

 Display

  • Liquid-crystal display: 7.5” dual-mode TFT display;
  • Viewing area: 152.4 mm × 114.3 mm;
  • Two "modes" depending on lighting conditions:
(1) Grayscale (B&W) reflective mode: for outdoor use—sunlight-readable; primarily lit from the front by ambient light; high-resolution (200 DPI), 1200(H) × 900(V) grayscale pixels; power consumption 0.1–0.2 watts;
(2) Color, backlight mode: for indoor use; primarily lit from behind by the LED backlight; built in sub-pixel sampling of the displayed color information results in a perceived resolution of approximately 984(H) × 738(V); power consumption 0.2–1.0 watts;
Note: web browser images are currently scaled up so that an image of very roughly [800 × 600] fills up the browser window.

Integrated peripherals

  • Keyboard: 80+ keys, 1.0 mm stroke; sealed rubber-membrane key-switch assembly;
  • Gamepad: Two sets of four-direction cursor-control keys;
  • Touchpad: Capacitance touchpad
  • Audio: Internal stereo speakers and amplifier; internal monophonic microphone; jacks for stereo external headphones and microphones.
    • Realtek ALC5631 audio codec (I2S)
  • Camera: integrated color video camera; 640 x 480 resolution at 30 FPS;
    • Independent (and undefeatable by software) display of microphone and camera recording status;
    • The camera and device driver support disabling AGC and automatic color balancing, to enable its use as a photometric sensor for educational applications;
    • Omnivision OV7670
  • Wireless Networking: Integrated 802.11b/g (2.4 GHz) interface; dual adjustable, rotating antennas support diversity reception;
    • Marvell 88w8686 WLAN module, with SDIO interface, on removable module;
    • Remains powered while the laptop suspends, waking the laptop if a packet addressed to it arrives.
    • Ad-hoc networking and 802.11s mesh support available
  • Accelerometer: ST LIS33 three axis accelerometer
  • Status indicators:
    • Power, battery, Wi-Fi, one software controlled (intended for onboard flash access), visible with lid open or closed;
    • Microphone In-Use, and Camera In-Use, visible when lid is open.
    • Light Sensor: a reverse biased LED.

 

External connectors

  • DC power: 6 mm (1.65 mm center pin) connector; 11 to 24 V input usable, –32 to +40 V input tolerated; power draw limited to 25 W; - see power connector dimensions at Battery and power.
    • Maximum Power Point Tracking alters voltage/current for maximum battery-charging power from solar panels
  • Headphone output: standard 3.5 mm 3-pin switched stereo audio jack;
  • Microphone input: standard 3.5 mm 3-pin switched stereo microphone jack; selectable 2 V DC bias; selectable sensor-input mode (DC or AC coupled);
  • USB: Three Type-A USB 2.0 connectors; Up to 1 A power supplied (total, available through a single connector);
  • Flash Expansion: full-size SD Card slot.

Battery

  • Pack type: 2 cell LiFePO4, approx. 6 V series configuration;
  • Capacity: 22 watt-hours (LiFeP);
  • Fully-enclosed “hard” case; user removable;
  • Electronics integrated with the pack provide:
    • Identification;
    • Battery charge and capacity monitoring chip (Maxim DS2756 data sheet);
    • Thermal and over-current sensors along with cutoff switch to protect battery;
  • Minimum 2,000 charge/discharge cycles (to 50 % capacity of new).

————————————————————————

  Source: http://wiki.laptop.org/go/XO-1.75

————————————————————————

 

EDIT