User:Alejandro Mery/Lapdock

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Design and manufacture an Open Source Mobility Accessory for HDMI sticks and development boards providing an inexpensive quality dumb "shell" with display, audio, input, usb and battery.

Rationale

Motorola's lapdock was a great idea, but it was conceived as a device-specific accessory, sold for around $250 and soon phased out. now this hard to find "accessory" is used to turn hdmi sticks and dev boards like the raspberry-pi and cubieboard into a "laptop". beside availability the major problem is the micro-male connectors which aren't only fragile but complicate to connect using inexpensive standard cables and your device ends up levitating over a tangle of cables and adapters. An as it assumes a phone is connected it kills the power of your toy when closing the lid.

ARM devices get faster, smaller and sexier by the day, and also cheaper and cheaper, and this reflects directly in sexy develoment boards and good dirt-cheap hdmi dongles, a market that is now so mainstream that even DELL announced one.

There is need (niche market, geeks) of a better solution, a lapdock with full size female hdmi and usb connector, good construction and good screen. Sourcing components of existing good laptops.

It has been proposed to design two flavours, a Tabdock (dumb large tablet, no keyboard/touchpad, no sata) and the actual Lapdock, sharing the same PCB.

Name

The Lapdock word is trademarked, so need a new name:

  • geekdock?
  • lapstick?
  • stickbook?
  • stickdock?
  • ...

Target connectable devices

Because of the assorted sizes and connector location the stick can't be inside the case, so the interface will be external. The least common denominator is HDMI video + audio, USB-Host 2.0 and 5V power.

  • A tv dongle (aka hdmi stick) usually has a male full-size HDMI connector and a couple of USB ports, one of which (OTG) can be used to power the device up to 0.5A, and optionally a dedicated 5V DC connector.
  • A (development) board usually has a female full-size HDMI connector, a dedicated 5V DC connector, a bunch of USB ports, and one usb device port (or OTG) that can sometimes also power the device up to 0.5A.

Even if it's not very common yet dongles and boards can include a SATA/eSATA port, but there are also inexpensive USB/eSATA adapters that can be plugged on one of the spare USB ports in the device, to not compete for USB bandwidth with the lapdock.

Target enclosures

common features

  • good display
  • good battery
  • HDMI in (video, audio, CEC)
  • USB 2.0 in
  • 12V DC in, 5.5/2.1mm connector.
    • flexible Voltage range would be welcomed
  • Powered USB out.
  • USB touchscreen
  • Camera

Tablet

  • 8-10"
    • 4:3 ?
    • issue: can't find any suitable panel!
    • issue: eDP to LVDS coverter will probably be required.
  • buttons?
  • rotation?
  • issues:
    • casework to stick the device parallel on the back instead of as a fragile "antenna" might be needed, or maybe the same VESA mount feature of the laptop variant?
  • ...

Laptop

  • 11-13"
  • solid enclosure
  • USB keyboard with assorted layouts available
  • USB touchpad
  • internally powered 2.5" SATA bay
  • eSATA out
  • VESA mount compatible holes on the back of the display to let you fix the stick/devboard
    • extension cables to keep the cablemess to a minimal with used fixed
    • easy to drill manually 3d-printable plastic plate compatible with the VESA mount where to screw or strap the stick/board and it's cables
  • ...

Specifications

Inputs

The idea is to stick the dongle directly, and then connect a USB cable. Development boards or dongles with female hdmi connector will require an HDMI cable as well. The point is make it easy to use by not requiring anything fancy.

  • Full size female HDMI connector (where to connect a normal HDMI stick directly) and optionally a DisplayPort connector
  • Full size female Type A USB 2.0 slave connector capable of feeding the device with power when used connected to an OTG port (even with the lid closed), leading to a USB hub.
  • Standard 12V/2A 5.5/2.5mm DC connector. (Ideally been able to take more than 2A if needed)
    • diskless devices might be perhaps powered from 5V/USB with display dimmed?

It would also be interesting to add eSATA, to connect an internal 2.5" SATA drive powered by the lapdock.

Video/Audio

From HDMI/DisplayPort input to an HDMI/eDP controller, and then:

  • 11-13" screen of at least 1080p (1920x1080) resolution
    • usable outdoor (matte?)
      • aim for the best ;-)
    • dream: option of using a compatible higher resolution panel
      • panels come with edid ;-)
  • stereo speakers
    • how to de with amp/volume control?
  • 3.5" headphone

USB

From the USB device port to a self-powered 7x USB 2.0 hub, then connected to:

  1. usb camera with mic
    • mainline linux support
    • mic also available in the 3.5" connector?
  2. full SD card reader
  3. Type A Host port capable of feeding >1A (2.1 possible?) even with the lid closed.
  4. Type A Host port.
  5. tbd ... standard usb/mini-pci-e socket ? --—amery (?) 09:51, 5 March 2013 (CET)
  6. tbd
    1. having two usb/mini-pci-e might be very useful for wifi, gps or 3g modems. so it might be important to wire antennas inside the cases and maybe one or two external connectors for real ones.
  7. USB 1.1 hub
    1. Near full-size quality (not bending!) keyboard
      • dream: option to source different layouts
    2. touchpad with mainline linux support
      • dream: two finger, middle button
    3. capacitive touch screen
      • resistive option?
      • tablets and phones have TS troubles when used plugged, need to avoid that here.
    4. tbd ... EC ? --—amery (?) 09:51, 5 March 2013 (CET)

Note: the USB device port needs to be fed too.

Power

  • battery capable of feeding the attached device and screen for at least 6h (is 10h too much asking?)
  • power the usb hub, the usb input port, and give ≥ 1A on at least one of the host ports.
  • battery indicator
  • avoid "interference" with TS
  • feed 2.5" SATA drive (SSD for the sake of power saving)

Hacking

  • easy to open up
  • pins to reprogram the EC
    • dream: EC reachable over USB
    • dream: STM32F based EC
      • e.g. stm32f107
  • schematics
  • OSHW?

Implementation proposals

PCB

Some options for the needed ICs are:

  • HDMI/LCD controller:
    • RTD2482D HDMI/LVDS controller
    • ANX7808 HDMI/eDP controller
      • SlimPort/USB support means we can use it as a USB display like DisplayLink? --—amery (?) 10:42, 21 February 2013 (CET)
  • USB 2.0 7x self-powered hub:
  • USB Charger
  • PMIC (12V to 3.3V + LiPo charger)
    • tbd

Screens

Battery

for 10W * 6h @ 3.3V:

Random Notes

  • eDP is better than LVDS/FPD-Link
  • DisplayPort is better than HDMI