2. Agenda
● Challenges in Modern Embedded Systems
● Overview of Erlang
● Erlang Embedded
● Q&A
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3. Challenges in Embedded Systems (I)
● Larger, more complex systems than ever before
● Multi-core processing
● Harder to develop for using the standard embedded
development flow
● Harder to utilise the full processing potential
● Much harder to debug (and fix!)
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4. Challenges in Embedded Systems (II)
● Increasingly higher degrees of heterogeneity in
terms of:
● Cores
● Hardware acceleration (GPU, co-processor etc)
● Interconnect
● Memory hierarchies
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5. Internet of Things (I)
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6. Internet of Things (II)
http://blogs.cisco.com/news/the-internet-of-things-infographic/
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7. Erlang?
● {functional, concurrent/parallel, garbage-collected,
soft real-time, fault-tolerant, distributed, message-
passing}
● First version developed in 1986
● Open-sourced in 1998.
● Battle-tested at Ericsson and many other companies
● Originally designed for Embedded Systems!
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8. Erlang Advantage (I)
● Declarative
● Functional programming language, high abstraction
level, concise readable programs.
● Concurrent and Parallel
● Highly scalable, transparent or explicit concurrency,
lightweight processes. Takes full advantage of
multicore architectures.
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9. Erlang Advantage (II)
● Robust
● Simple and consistent error recovery and supervision
hierarchies, built-in fault tolerance.
● Portable, Distributed
● Runs on a variety of platforms, network-aware
runtime, supports heterogeneous networks.
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10. Erlang Advantage (III)
● External Interfaces
● NIFs and ports used to interface external world to the
Erlang runtime.
● Soft Real-Time
● Response time (can be) in the order of milliseconds,
per-process garbage collection.
● Hot-code loading
● Dynamic reconfiguration.
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11. Erlang, the Maestro
(flickr/dereckesanches)
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12. External Interfaces
● Native Implemented Functions (NIFs) and ports
used to interface external world to the Erlang
runtime.
Erlang VM
app
hw_if hw_driver.c
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13. #include “stats.h”
Source: http://embedded.com/electronics-blogs/programming-pointers/4372180/Unexpected-trends
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14. Actor Model
● Proposed in 1973 by Hewitt, Bishop, and Steiger
● “Universal primitives of concurrent computation”
● Building blocks for modular, distributed and concurrent
systems
● No shared-state, self-contained and atomic
● Implemented in a variety of programming languages
● Erlang, Scala (AKKA), Java (Kilim), Ruby (Celluloid), C++11 (libcppa)
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15. Actor Model
● Asynchronous message passing
● Messages kept in a mailbox and processes in the
order they are received in
● Upon receiving a message, actors can:
● Make local decisions and change internal state
● Spawn new actors
state
● Send messages to other actors functionality
mailbox
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16. Example: GPIO
proc_a
{in
it,
17
,o
ut
pu
t}
GPIO
pin17
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17. Example: GPIO
proc_a proc_b
}
,l ow
7
{s ,1
ta te
te {s
ta
,1
7,
hi proc_c
gh }
} ,1 7, high
GPIO {state
pin17
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18. GPIO “Proxy”
● Replaces the “locks” in traditional sense of
embedded design
● Access control/mutual exclusion
● Can be used to implement safety constraints
● Toggling rate, sequence detection, direction control,
etc.
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19. TI OMAP Reference System
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20. Fine Grain Abstraction
● Advantages
● Application code becomes simpler
– Concise and shorter modules
– Testing becomes easier
– Code re-use (potentially) increases
● Disadvantages
● Architecting fine grain systems is difficult
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21. Erlang Embedded
“The aim of this KTP project is to bring
the benefits of concurrent systems
development using Erlang to the field
of embedded systems; through
investigation, analysis, software
development and evaluation."
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24. Interested in Erlang?
● http://www.erlang.org/doc/
● http://learnyousomeerlang.com/
http://www.youtube.com/watch?v=xrIjfIjssLE :)
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25. Erlang Embedded Training Stack
● A complete package for people interested in
developing the next generation of
concurrent/distributed Embedded Systems
● Training Modules
Erlang Embedded Framework
● Embedded Linux Primer
Erlang/OTP 101
● Erlang/OTP 101
● Erlang Embedded Framework
Embedded Linux Primer
● Hardware included!
Hardware Platform
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26. Thank you
● www.erlang-embedded.com
● embedded@erlang-solutions.com
● @ErlangEmbedded
“ Any sufficiently complicated concurrent program in
another language contains an ad-hoc, informally-
specified, bug-ridden, slow implementation of half of
Erlang.
– Robert Virding
Co-Inventor of Erlang
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