AdaCore Blog

12 entries tagged with #Tasking

by Claire Dross

Using Pointers in SPARK

In this blog post, I will present one of the most interesting additions to the community 2019 version of SPARK: pointer support. One of the core assumption in SPARK has always been the absence of aliasing, so adding pointers without breaking this assumption was quite a challenge. I will explain how this was achieved using an ownership model for pointers (like is done in Rust) through small examples.

#VerificationTools   

by Allan Ascanius, Per Dalgas Jakobsen

Winning DTU RoboCup with Ada and SPARK

The Danish Technical University has a yearly RoboCup where autonomous vehicles solve a number of challenges. We participated with RoadRunner, a 3D printed robot with wheel suspension, based on the BeagleBone Blue ARM-based board and the Pixy 1 camera with custom firmware enabling real-time line detection. Code is written in Ada and formally proved correct with SPARK at Silver level.

#Robotics    #Ada    #SPARK   

by Rob Tice

AdaFractal Part 2: Fixed Point and Floating Point Math Performance and Parallelization

In Part 1 of this blog post I discussed why I chose to implement this application using the Ada Web Server to serve the computed fractal to a web browser. In this part I will discuss a bit more about the backend of the application, the Ada part.

#Fixed Point    #Floating Point    #Tasking    #Fractal    #AWS    #Generics   

by Fabien Chouteau

There's a mini-RTOS in my language

The first thing that struck me when I started to learn about the Ada programing language was the tasking support. In Ada, creating tasks, synchronizing them, sharing access to resources, are part of the language

#Ada    #Ravenscar    #embedded    #STM32   

by Fabien Chouteau

Ada on the first RISC-V microcontroller

Updated July 2018

#Embedded Development    #Ada    #RISC-V   

by Emmanuel Briot

New strings package in GNATCOLL

This post describes the new GNATCOLL.Strings package, and the various optimizations it performs to provide improved performance.

#gnatcoll    #strings    #Ada   

by Jerome Guitton, Jérôme Lambourg, Joel Brobecker

Simics helps run 60 000 GNAT Pro tests in 24 hours

This post has been updated in March 2017 and was originally posted in March 2016.

#Simics    #WindRiver    #GNAT Pro   

by Fabien Chouteau, Arnaud Charlet, Yannick Moy

SPARK Tetris on the Arduboy

One of us got hooked on the promise of a credit-card-size programmable pocket game under the name of Arduboy and participated in its kickstarter in 2015. The kickstarter was successful (but late) and delivered  the expected working board in mid 2016. Of course, the idea from the start was to program it in Ada , but this is an 8-bits AVR microcontroller (the ATmega32u4 by Atmel) not supported anymore by GNAT Pro. One solution would have been to rebuild our own GNAT compiler for 8-bit AVR from the GNAT FSF repository and use the AVR-Ada project. Another solution, which we explore in this blog post, is to use the SPARK-to-C compiler that we developed at AdaCore to turn our Ada code into C and then use the Arduino toolchain to compile for the Arduboy board.

by Piotr Trojanek

Verifying Tasking in Extended, Relaxed Style

Tasking was one of the big features introduced in the previous release of SPARK 2014. However, GNATprove only supported tasking-related constructs allowed by the Ravenscar profile. Now it also supports the more relaxed GNAT Extended Ravenscar profile.

#Language    #Formal Verification    #SPARK   

by Fabien Chouteau

Make with Ada: ARM Cortex-M CNC controller

I started this project more than a year ago. It was supposed to be the first Make with Ada project but it became the most challenging from both, the hardware and software side.

#Makers    #Ada    #STM32    #ARM    #Embedded Development   

by Florian Schanda

SPARK 2014 Rationale: Variables That Are Constant

The SPARK tools now support yet another feature that allows users to better specify the intended behavior of their programs. This new feature enables users to declare that specific variables can only be updated during the elaboration of their enclosing package. Read on if you want to know more...

#Formal Verification    #Language    #SPARK   

by Tristan Gingold, Yannick Moy

Tetris in SPARK on ARM Cortex M4

Tetris is a well-known game from the 80's, which has been ported in many versions to all game platforms since then. There are even versions of Tetris written in Ada. But there was no version of Tetris written in SPARK, so we've repaired that injustice. Also, there was no version of Tetris for the Atmel SAM4S ARM processor, another injustice we've repaired.

#SPARK    #ARM