Embedded Linux

Anuj Deshpande*

Agenda

• History
• Players
• Common features
• Gotchas
• Making your own
  • Distro
  • Drivers
  • Hardware
  • Should you?
• uController vs uProcessor
• Projects you should know
• Products*
• Resources

Raspberry Pi hit F5

The race to be the cheapest computer

1. $25 - Pi Model A
2. $9 - CHIP
3. $5 - PiZero
4. free ?

1. Model A/Model B - 256
2. Model A/Model B - 512
3. Model A+/Model B+
4. Model B 2  
5. Model B 3
6. Compute module
7. piZero

1. BeagleBoard
2. BeagleBoard -xM
3. BeagleBone White
4. BeagleBone Black
   1. Green
   2. Blue
   3. Green wireless
5. BeagleBoard -x15

Common features

• Memory
• eMMc vs SD
• pins
• clock
• GPU
• community

aka How to pick one ?

Gotchas

1. 'Slightly' more complicated than
   pinMode(13,HIGH)
2. There are other processes you need to respect
3. You can use any language, follow any guidelines, but you shouldn't (NASA)
4. Timing isn't what you thought it's going to be (preempt, xenomai)

Making your own

• Linux From Scratch
• Free electrons
• Yocto

Distro

Making your own

• Is it even possible for your board ?
• What should you expect ?
  • Price
  • Complexity
  • Certifications

Hardware

Making your own

• How low can you go ?
• • userspace - only one process will use
  • kernel space - needs interrupts
• Device trees
  • What's capemgr ? 

Drivers

LDD3

More often than not, the silicon manufacturer subsidizes

• TI
• Broadcom
• Allwiner

uProcessor

1. Power consumption is too much 
2. Assembly is going to cost you a bomb
3. Do you really need so much ?

uController

1. Security is tough 
2. DIY assembly totally possible
3. Are you sure you are going to fit everything in this ?

Projects you should know about

• Snappy Ubuntu Core
• Android (duh!)
• Buildroot, Yocto
• OpenWRT
• 96boards

Products*

*that started out on a SBC and are "commercially" available

Ember

Remix Mini

and more

A better way

or a more common approach

1. Let people buy the board
2. Provide images/software
3. Sell kits/services/cloud

Smart Cities

1. Kiosks & vending machines
2. Citizen science
3. Cars (and bikes?)
4. Routers/access points
5. Displays

@anujdeshpandey

slides.com/anujdeshpande/embedded-linux