Controlling a Train Model with GNAT GPL for Raspberry Pi 2

Tristan GingoldPresented by

Agenda• GNAT GPL 2015

• Model train

• Demo

AdaCore FOSS contributions• AdaCore maintains the Ada front-end of GCC

• AdaCore also contributes patches to the GCC middle and backend

• Mainly bug fixes and contributions related to Ada

• All the software developed by AdaCore is Libre software

• Every year, AdaCore releases GNAT GPL

• A GPL version of AdaCore environment for some platforms

What is GNAT GPL ?• GNAT compiler, based on gcc sources + AdaCore patches

• + IDE (gps), builder, ASIS tools…

• Released every year (June-ish)

• Many add-ons available: AWS, ASIS, GNATbench, Aunit, GNATcoll, GtkAda, XML/Ada, Florist, SPARK

Targeted audience• Academics: members of the GAP program.

• Students

• Free Software / Open Source developers

The license of the GNAT GPL runtime is GPL. Software built with GNAT GPL and linked with its runtime must follow the GPL.

And some extras• We sometimes release GNAT GPL for a new platform

• Not sold (ie not a GNATPro product)

• Just for the community

• Or for a marketing purpose…

• In the past: GNAT-GPL for Lego Mindstorms

GNAT GPL 2015• New: GNAT GPL for Raspberry Pi 2

• Popular platform

• Now uses a modern core: Cortex-A

• Cross compiler, hosted on x86-linux, targeting armhf-linux

• Full runtime

Raspberry Pi Model B+ V1.2

USB port

USB port

Ethernet

HDMI

GPIO

ARM Cortex-A7 4 Cores

Railway safe signaling Demo

2015: STM32F429 board demo

Railway Signaling

Train

Absolute block

Permissive block

Spawn station

Free block

Touch to switch

Why ?• To prove the absence of collision using SPARK 2014

• To get closer to customer experience

• And mainly to play with our new Raspberry Pi 2 port !

Hardware• Electrical railway modelling kit

• On-off power relay to control trains

• Hall effect sensors to detect trains

• Turnout motors to control switches

• Raspberry Pi 2

Hardware Raspberry Pi 2On-off power FETs

Turnout motors to control switches

Hall effect sensors to detect trains

One way track model

Controlled section On/Off

Uncontrolled section

always on

Sensor

Slow train coming

Slow train going on

Slow train detected

Slow train still going

Slow train detected again

Slow train going away

Turnout the tricky part

Turnout the tricky part

Railway layout

Software designwith SPARK_Mode

Signaling Manager (protected object)

Sensor monitoring (Task)

SDL Graphical Interface (task)

Train Simulator (Task)

HW interface Raspberry Pi 2 GPIO

SPARK proof

Real life validation

Real life validation

Conclusion• It works!

• Ada 2012 mixed with SPARK 2014 are ready for the industry

• Easy to access and learn technology

• Demo sources will be available on GitHub

• Have a look at AdaCore University • http://university.adacore.com/