Portable Handheld QWERTY Computer
The idea is to have a portable (pocketable) handheld device similar in size to a PDA or cellular phone with reduced QWERTY keyboard. Viable form factors (and examples) are:
- Clamshell Microlaptop (Zipit Z2, NanoNote, DragonBox Pyra, Openbox Pandora, HTC Universal)
- Candybar (Malti, Nokia E71, BlackBerry)
- Slider (Motorola Photon Q, HTC Dream)
- Likely difficult/costly to implement sliding mechanism
Mailing List Discussion: - http://lists.phcomp.co.uk/pipermail/arm-netbook/2016-August/011793.html - http://lists.phcomp.co.uk/pipermail/arm-netbook/2016-September/011917.html
Minimum Feature Set
- Hardware QWERTY keyboard
- Keyboard Matrix IC Options
- TCA8418 I2C Keypad Matrix IC
- STM32F072 with custom firmware
- Tactile Snap-Dome Keypad Array with Silicone Button Overlay
- Snaptron Peel-N-Place Custom Dome Array
- Dome examples in use (NanoNote2 [1] [2], Zipit Z2)
- DIY Silicone Keypad Overlay [1]
- Mouse Emulation
- Backlight
- Possible Keypad Layout Examples
- Keyboard Matrix IC Options
- LCD
- Resolution >= 640x480
- LH350WS1-SD01 MIPI 3.5" 640x960
- CFAF480800T07-043T-TS RGB 4.3" 480x800 w/Resistive Touchscreen
- Low Resolution
- CFAF320480C5-035T-TS RGB 3.5" 320x480 w/Resistive Touchscreen
- SSD2828QN4 RGB to MIPI Converter IC (Datasheet)
- a20_pad_std_v1_1.pdf from here has reference design on page 20
- arm-netbook Reference
- linux-sunxi wiki
- Resolution >= 640x480
- Touchscreen (resistive)
- STMPE811 touch controller/gpio expander
- Audio (via USB)
- TRRS Headphone Jack
- Loudspeaker (mono or dual stereo)
- USB Host Port(s)
- MicroSD Socket
- Power Circuitry
- Power Path Management & LiPo Charging IC
- Possible option TI BQ24266 (USB or 12V input)
- LiPo Battery
- Fuel Gauge IC?
- LiPo to 5V Boost Circuit
- Power Path Management & LiPo Charging IC
Optional / Extra Features
- Bonus points if it is also "ruggedized": waterproof, shockproof, etc.
- Trackpoint or similar, for using the mouse cursor without needing to touch the screen, as on the Pyra
- Built-in Wifi (SKW17 module)
- Cellular Phone Module (voice and/or data capability)
- Simcom SIM5320 3G (Adafruit Fona 3G, Product Page)
- Gemalto PLS8 4G (Product Page)
- SEW291 3G (Alibaba)
- Sensors
- Ambient Light Sensor (auto adjust backlights)
- Accelerometer/Gyro (MPU6050)
- Vibration Motor
- GPS module
- Camera and LED Flash
- Bluetooth module
- Audio
- Line Input
- Microphone
- Ear Speaker (for voice calling)
Notes, Comments
Goes without saying that it should be licensed as a Free Cultural Work, i.e. under GPLv3 or suchlike.
Why would it be great? Well, traditionally, people using a PDA had to synchronise their information between their desktop or laptop and the PDA, e.g. via a cable or IrDA or Bluetooth. Now lots of people do this via "the cloud", but that just means going via someone else's computers, so unless that system is implemented on a zero-knowledge basis using client-side encryption basis, then whoever else's computers are being used also gets to see the information. That might be really private stuff, like contacts and appointments and correspondence. With EOMA68, that problem would be solved: while out and about where a laptop would be too bulky but a PDA wouldn't, just have the EOMA68 card in the PDA housing. When at a desk, put it in the desktop or laptop housing. No need to sync!
That means:
- No loss of privacy
- Less need for energy-intensive data centres
- No need to have two computers when one would do (less e-waste)
- No worries about race conditions due to data getting updated on desktop and PDA before syncing.
- No headaches, essentially!
Pad listing/discussing specs and questions: https://public.pad.fsfe.org/p/eoma68_handheld (should be imported into wiki at somepoint, theres export options, so it should be copy and paste or direct wiki import maybe? anyway i expect it will work out ;).