Ansaldo STS is a railway signalling company founded in 1853 with approximately 4000 employees globally. It develops signalling systems that require high safety levels up to SIL4 and product lifespans of around 30 years. Ada is used extensively in its software, including in simulators with 800KLOC of code, vital computers with up to 600KLOC, and applicative programs from 90-200KLOC. Development environments include IDEs like GPS and Eclipse along with static analysis, testing, and metric tools to ensure safety and quality for critical railway systems.

1. Ada at Ansaldo STS Jérôme Touet, software engineer GNAT Industrial User Day, September 25th 2014

2. +TS
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Ansaldo STS: Overview
•Founded in 1853
•Activity: signalling and supervision of railway and urban traffic.
•Main shareholder: Finmeccanica
•~4000 employees
•Global presence

3. Signalling Systems
•Type of systems:
•Interlocking
•Mainlines and high speed (ERTMS, TVM, …)
•Mass transit (CBTC, …)
•Constraints:
•High safety level (SIL4)
•Assessment process (norm EN 50128)
•Product life of ~30 years
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4. Use of Ada
First case: simulator
•~800 Kloc (kernel) + ~300 Kloc (HMI)
•50% Ada 83 + 50% Ada 95 (+ 2005 + 2012)
•GTKAda, AWS, XMLAda, Win32Ada
•GNAT 7.2 for Windows target
•IDE: Eclipse
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5. Use of Ada
Second case: platform equipment (Available Vital Computer)
•Up to 600 Kloc
•Mainly Ada 83 + Ada 95
•Architectures:
•PowerPC (wayside equipments): GNAT compiler
•Coldfire (onboard equipments): GHS compiler
•IDE: GPS, Understand for Ada
•Safety constraints (SIL4)
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6. Use of Ada
Third case: applicative program
•From ~90 to ~200 Kloc
•Ada 83 and Ada 95 (new applications)
•Architectures:
•PowerPC (wayside equipments): GNAT compiler (6.1.1)
•Coldfire (onboard equipments): GHS compiler
•IDE: GPS, Understand for Ada
•Safety constraints (SIL4): « basic » use of Ada
•No object, no tasking, few generic
•Sometimes interfaced with C code
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7. Development Environment
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Ada
Static Analysis
Test
Metrics
Compiler
IDE
•GPS (+ plug-ins)
•Eclipse
•Understand for Ada
•GNAT
•Green Hills Software
•RTRT
•AUnit
•Adacontrol
•Polyspace
•CodePeer
•Understand for Ada
•Logiscope
•GNAT metric

8. CodePeer evaluation
•Integrated to GPS
•Bottom-up approach (allow the check of a unique package)
•Configurable
•Level of analysis
•Message filtering
•Keep track of reviews
•EN 50128 qualification material
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9. CodePeer evaluation
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SERVER (nightly run)
DEV 1
DEV 2
OUTPUTS
Web Server
local view
local view
review

10. THANK YOU FOR YOUR ATTENTION