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I'm new to electronics (outside of twiddling with Arduino and a basic college course - I'm more of a software guy) and I'm attempting to build a custom, extremely low-powered, extremely thin, laptop.

The ideal is a keyboard, a microcontroller or some chip running command-line Linux distribution (potentially uClinux) and an LCD display. It could potentially run on double A batteries for the time being. It would also need wifi access.

My current biggest question is what kind of microcontroller (or other device) I should look for as the brain of the device. I've considered just sticking in a Raspberry Pi, but that's actually much larger than I would like, so I'm willing to attempt a custom-soldered solution. Are there sufficient ones which already have Linux installed? Are there some which have enough input pins / proper inputs for a keyboard / LCD display?

I'm also willing to write a driver or two for the keyboard, LCD, etc. as necessary, FYI.

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    \$\begingroup\$ Extremely low-powered, extremely thin laptops are commonly called tablets. Andoid tables are powered by the Linux Kernel. \$\endgroup\$
    – Turbo J
    Commented Jan 5, 2013 at 3:47
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    \$\begingroup\$ Bunnie Huang is building his own laptop - you might get some useful ideas from his blog: bunniestudios.com/blog/?p=2686 \$\endgroup\$
    – pault
    Commented Jan 5, 2013 at 4:24
  • \$\begingroup\$ "Could potentially run on AA batteries" - if you want to achieve this you'll need to plan it very carefully in terms of power consumption. The raspberry pi consumes several hundred milliamps. \$\endgroup\$
    – pjc50
    Commented Jan 5, 2013 at 11:09
  • \$\begingroup\$ Running AA batteries will make your device extremely thin? I won't even consider the fact that AA batteries won't last you more than an hour or two, maybe less. That said, it's definitely an interesting project. I would suggest looking into LiPo battery packs. Very cheap, easily rechargeable, and can deliver a lot of power in small and customizable form factors. Some LiPo packs can come as thin as 0.4 mm, although they may only provide ~200 mA, but you don' have to go that extreme. \$\endgroup\$
    – capcom
    Commented Jan 13, 2013 at 16:34

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For anything to run linux, it can't be a simple 8 or 16 bit microocntroller. Your best bet is an ARM based system, in particular Cortex A8 or A9. Basically aside from the raspberry pi you've got beagle board, beagle bone, panda board and a few similar other boards.

I'm not sure there is a custom apps processor module available in general. If you're an OEM then of course you can find something.

If you are willing to build your own solution you can make it very small.

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  • \$\begingroup\$ I was attracted originally to the beagle bone since it comes pre-installed with a linux distro, saving me some time / effort. Is there a simple way to interface that with a basic LCD display so I could actually peer into it? \$\endgroup\$ Commented Jan 5, 2013 at 18:24
  • \$\begingroup\$ @Gustavo Litovsky please suggest a ARM controller for laptop as your answer suggests. Can you please also provide references of any laptops running on ARM CPU \$\endgroup\$ Commented Sep 14, 2018 at 9:21
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Microcontrollers would not be a good choice for a laptop. They are good for embedded control and not for personal computer. To build a laptop, you would need other peripheral controller chips like drive controller, display controller, I/O controller, etc. These other chips may not interface with a "microcontroller" as cleanly.

To build a effective laptop you would be better off using a microprocessor. Further, you can buy a bare-bone kit and build your own laptop.

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  • \$\begingroup\$ thank you for the info - are you saying then that I would want the microprocessor as a hub for the other controllers you mentioned (drive, display and I/O controllers)? \$\endgroup\$ Commented Jan 5, 2013 at 18:20
  • \$\begingroup\$ Yes, you would need a microprocessor along with its chipset. \$\endgroup\$ Commented Jan 6, 2013 at 21:11
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AA batteries don't have enough capacity. When you're using the LCD backlight (and you will be) the device will consume probably around 300mA - 500mA, depending on peripherals and other hardware. Using AA batteries of possibly 1500mAh you would be done in a few hours the first time, the second time in like one hour. Use a LiPo accu on 3.7V with a charge pump to 5V, it is flatter and has more capacity.

When you're using uClinux, the FAQ and Getting Started pages on their webpage can help you out on what device you should use: an ARM controller.

However I would recommend you to build your own OS with only the functions you need - it would be way faster and it's more fun to make :-)

I'm building my own laptop-ish device, CText. This is my setup, you might find it interesting when you're going to build it from scratch with your own OS:

  • A PIC microcontroller keys which interfaces the keyboard of an old psion 5mx series
  • A PIC microcontroller graphics which interfaces an LCD screen
  • A PIC microcontroller main which calculates everything and communicates with the other PICs (over I2C), and handles RAM, SD card memory, RS232 communication, etc.

Wi-Fi access using a microcontroller is a bit hard, but there will be modules available on the net.
However you could also decide to use a chip with a USB peripheral to connect to your android phone (if you have one) and use the internet of the phone. You can build your own app to do this.

Updates on this project can be found here: http://camilstaps.nl/topic/electronics/electronics-projects/ctext/

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  • \$\begingroup\$ thanks for the tips! are there similar modular components to "keys", "graphics" etc., which are ARM and not PIC based? \$\endgroup\$ Commented Jan 5, 2013 at 18:21
  • \$\begingroup\$ I'm sorry I wasn't clear. I called the PICs that way, but I have to program them myself. You of course can program ARM controllers which have the same functions. Howevery, ARM is a bit stronger than PIC. You might be able to put keys and graphics functions (in computer terms, stdin and stdout) in one ARM controller, while I need two PICs for that. But main point is that since there is no software available, you've to write it yourself, and that can be done on ARM as well as PIC :-) \$\endgroup\$
    – user17592
    Commented Jan 5, 2013 at 22:24

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