This document summarizes a case study presented on the design of industrial instrumentation systems using multicore processors. Key aspects discussed include the use of aspect-oriented design to enable parallel hardware and firmware development, an event-driven programming model, and static memory allocation to guarantee worst-case performance. Performance results demonstrated low defect rates, high design reuse, and the ability to rapidly develop new products through a fully parallel development process.

1. Case Study: Alfa Instrumentos Multicore Industrial
Instrumentation
Thursday, April 25, 13

2. Design West 2013
Case Study: Alfa Instrumentos
Mul=core Industrial Instrumenta=on
Jonny Doin -­‐ Principal Engineer
Thursday, April 25, 13

3. Industrial Instrumenta.on
Case Study
In this class a Case Study will be shown of a family of
Industrial Instrumenta.on systems developed in the
course of the last 4 years.
Some design decisions will be discussed, along with
basic Architectural and Methodology aspects.
The results will be shown in the form of some
performance and field data.
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4. Case Study
Agenda
• Aspect Oriented Design
• Mixed Signal Hardware Design
• Asymmetric Mul. Core
• Bare-­‐Metal Firmware
• Event-­‐Driven Programming
• Sta.c Memory Alloca.on
• Hardware/Firmware co-­‐design
• Some performance data
Thursday, April 25, 13

5. Case Study
Aspect Oriented Design
AOD is more commonly found in large VLSI circuit
design.
• Design paradigm that decomposes a logic design into
concerns, and analyzes the cross-­‐cuOng concerns between
design units;
• We loosely apply AOD concepts into all levels of our designs,
from mixed-­‐signal hardware design, PCB rou.ng, and
firmware design;
• AOD enabled us to do parallel implementa.on of hardware
and firmware, allowing several engineers to work on the same
design, accelera.ng design cycles;
Thursday, April 25, 13

6. Case Study
Aspect Oriented Design
AOD also helps maintaining integrity of large
firmware projects.
• Correct aspect decomposi.on ensures scalability of the logic
design, by helping to maintain modularity and concern
separa.on;
• Recogni.on of aspect cross-­‐cuOng level is important to
achieve high modularity and design reuse;
• Helps to maintain design integrity along the evolu.on and
maintenance;
• Helps to realize the scalability of a given architecture;
Thursday, April 25, 13

7. Case Study
Mixed-­‐Signal Hardware Design
For precision instrumenta.on, you need precision
mixed-­‐signal techniques.
• Selec.ng suitable components is just part of the answer;
• Ground and power domains have to be carefully designed;
• EMC and EMI/RFI techniques for the Industrial environment;
• Minimiza.on of self-­‐inflicted noise;
• The PCB itself is the most important electronic component of
a system;
• Correct handling of the analog design will help achieve
datasheet performance of ADCs and SPICE models;
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8. Case Study
Asymmetric Mul.-­‐Core
In mission cri.cal systems, resilience and failure
containment are key factors to high reliability.
• Separa.on of subsystems into different cores isolates
processing domains;
• Different subsystems have different processing needs;
• Failure containment at subsystem level is facilitated;
• Core applica.on is isolated from external threats;
• Higher modulariza.on, helps deriva.ve models;
• Fieldbus communica.ons, TCP/IP hardware, USB D/H, DSP;
Thursday, April 25, 13

9. Case Study
Bare-­‐Metal Firmware
Industrial mission-­‐cri.cal systems have severe
constraints on down.me. Component reliability is a
key factor that affects the en.re produc.on chain.
• We decided for a bare-­‐metal architecture as a means of full
control of the firmware implementa.on;
• Fast reac.on to fixing design flaws and bugs is essen.al;
• However, a high level of abstrac.on and modularity is
employed;
• OOD is used throughout the system;
Thursday, April 25, 13

10. Case Study
Event-­‐Driven Architecture
We use an event-­‐driven architecture, similar to the
processing paradigm of a Hardware Descrip.on
Language simulator.
• Sequen.al processes are executed when input signals change;
• The use of processes and signals to describe firmware result in
a processing paZern that achieves cpu load balancing;
• It also results in a clear separa.on of aspects, helping to
maintain modularity and fostering design reuse;
• Is very scalable, allowing systems of 100s of thousands of lines
of code to be managed with low local complexity;
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11. Case Study
Sta.c Memory Alloca.on
It is paramount in a mission cri.cal system that
resource starva.on never occurs.
• RAM alloca.on is the most cri.cal resource;
• Dynamic alloca.on regimes with high availability can be very
difficult to verify:
• Usage paZerns cannot be reliably covered for all cases;
• Memory leak and fragmenta.on can s.ll occur;
• A sta.c memory alloca.on guarantees worst case scenario
and helps achieve full verifica.on of the logic;
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12. Case Study
Hardware/Firmware co-­‐design
Using the AOD techniques, and highly modular
firmware, full Hardware/Firmware co-­‐design was
possible.
• Firmware is developed ahead of hardware;
• Tes.ng and integra.on yields almost 100% compliance on first
integra.on tests;
• The process reduces cost of deriva.on of new products;
• Reuse of hardware subsystems is reflected in reuse of firmware
subsystems;
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13. Case Study
Some examples
-­‐ ADC, Ethernet,
-­‐ USB Host/Dev,
-­‐ Fieldbus,
-­‐ Cortex-­‐M4
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14. Case Study
Some examples
-­‐ High res ADC,
-­‐ Profibus,
-­‐ ARM7
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15. Case Study
Some examples
-­‐ Weigh Indicator,
-­‐ Very robust
-­‐ Heavy-­‐duty environments
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16. Case Study
Some examples
-­‐ Subcircuits are designed, prototyped and
tested as separate circuits, and are used in
the main development of finished
products.
-­‐ PCB-­‐level IP
-­‐ Allows many engineers working in the
same PCB design
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17. Case Study
Some Performance Data
Using the exposed techniques (AOD, OOD, Co-­‐Design, Event-­‐
Driven Architecture), some important results have been
achieved:
• Extremely low field defect rate;
• High design reuse, in diverse equipment lines;
• Fast spinoff of new boards;
• Full parallel development process, with several engineers working at the same
.me in the same project subsystem;
• Very high level of uniformity in the logic descrip.on, even for large designs;
• Maintained high quality of implementa.on, recognized by the customers;
Thursday, April 25, 13

18. Design West 2013
THANK YOU
Jonny Doin
jonnydoin@gmail.com
Thursday, April 25, 13