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Last week, the programmer Hillel posted a challenge (the link points to a partial postmortem of the provided solutions) on Twitter for someone to prove a correct implementation of three small programming problems: Leftpad, Unique, and Fulcrum.
PolyORB, AdaCore's versatile distribution middleware, now lives on Github. Its new home is https://github.com/AdaCore/polyorb
So you want to use SPARK for your next microcontroller project? Great choice! All you need is an Ada 2012 ready compiler and the SPARK tools. But what happens when an Ada 2012 compiler isn’t available for your architecture?
The micro:bit is a very small ARM Cortex-M0 board designed by the BBC for computer education. It's fitted with a Nordic nRF51 Bluetooth enabled 32bit ARM microcontroller. At $15 it is one of the cheapest yet most fun piece of kit to start embedded programming.
Bitcoin is getting a lot of press recently, but let's be honest, that's mostly because a single bitcoin worth 800 USD in January 2017 was worth almost 20,000 USD in December 2017. However, bitcoin and its underlying blockchain are beautiful technologies that are worth a closer look. Let’s take that look with our Ada hat on!
This blog post is part one of a tutorial based on the OpenGLAda project and will cover some the background of the OpenGL API and the basic steps involved in importing platform-dependent C functions.
Every year, free and open source enthusiasts gather at Brussels (Belgium) for two days of FLOSS-related conferences. FOSDEM organizers setup several “developer rooms”, which are venues that host talks on specific topics. This year, the event will happen on the 3rd and 4th of February (Saturday and Sunday) and there is a room dedicated to the Ada programming language.
Libadalang has come a long way since the last time we blogged about it. In the past 6 months, we have been working tirelessly on name resolution, a pretty complicated topic in Ada, and it is finally ready enough that we feel ready to blog about it, and encourage people to try it out.
Summary The Ada IoT Stack consists of an lwIp (“lightweight IP”) stack implementation written in Ada, with an associated high-level protocol to support embedded device connectivity nodes for today’s IoT world. The project was developed for the Make With Ada 2017 competition based on existing libraries and ported to embedded STM32 devices.
As we see the importance of software grow in applications, the quality of that software has become more and more important. Even outside the mission- and safety-critical arena customers are no longer accepting software failures (the famous blue screens of death, and there are many...). Ada has a very strong answer here and we are seeing more and more interest in using the language from a range of industries. It is for this reason that we have completed our product line by including an entry-level offer for C/C++ developers wanting to switch to Ada and reinforced our existing offer with GNAT Pro Assurance for programmers building the most robust software platforms with life cycles spanning decades.
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
Summary The Hexiwear is an IoT wearable development board that has two NXP Kinetis microcontrollers. One is a K64F (Cortex-M4 core) for running the main embedded application software. The other one is a KW40 (Cortex M0+ core) for running a wireless connectivity stack (e.g., Bluetooth BLE or Thread). The Hexiwear board also has a rich set of peripherals, including OLED display, accelerometer, magnetometer, gryroscope, pressure sensor, temperature sensor and heart-rate sensor. This blog article describes the development of a "Swiss Army Knife" watch on the Hexiwear platform. It is a bare-metal embedded application developed 100% in Ada 2012, from the lowest level device drivers all the way up to the application-specific code, for the Hexiwear's K64F microcontroller. I developed Ada drivers for Hexiwear-specific peripherals from scratch, as they were not supported by AdaCore's Ada drivers library. Also, since I wanted to use the GNAT GPL 2017 Ada compiler but the GNAT GPL distribution did not include a port of the Ada Runtime for the Hexiwear board, I also had to port the GNAT GPL 2017 Ada runtime to the Hexiwear. All this application-independent code can be leveraged by anyone interested in developing Ada applications for the Hexiwear wearable device.
While we are working very hard on semantic analysis in Libadalang, it is already possible to leverage its lexical and syntactic analyzers. A useful example for this is a syntax highlighter.
When things don’t work as expected, developers usually do one of two things: either add debug prints to their programs, or run their programs under a debugger. Today we’ll focus on the latter activity.
For those users of the GNAT GPL edition, we are pleased to announce the availability of the 2017 release of GNAT GPL and SPARK GPL.
The RISC-V open instruction set is getting more and more news coverage these days. In particular since the release of the first RISC-V microcontroller from SiFive and the announcement of an Arduino board at the Maker Faire Bay Area 2017.
In my previous blog article, I exposed some techniques that helped me rewrite the Crazyflie’s firmware from C into Ada and SPARK 2014, in order to improve its safety.
User friendly strings API In a previous post, we described the design of a new strings package, with improved performance compared to the standard Ada unbounded strings implementation. That post focused on various programming techniques used to make that package as fast as possible.
This post has been updated in March 2017 and was originally posted in March 2016.
Following the current trend, the GNATcoverage project moves to GitHub! Our new address is: https://github.com/AdaCore/gnatcoverage
While searching for motivating projects for students of the Real-Time Systems course here at Universitat Politècnica de València, we found a curious device that produces a fascinating effect. It holds a 12 cm bar from its bottom and makes it swing, like an upside-down pendulum, at a frequency of nearly 9 Hz. The free end of the bar holds a row of eight LEDs. With careful and timely switching of those LEDs, and due to visual persistence, it creates the illusion of text... floating in the air!
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.
The Ada Drivers Library (ADL) is a collection of Ada device drivers and examples for ARM-based embedded targets. The library is maintained by AdaCore, with development originally (and predominantly) by AdaCore personnel but also by the Ada community at large. It is available on GitHub and is licensed for both proprietary and non-proprietary use.
AdaCore will be hosting a joint webcast next Monday 12th December 2pm ET/11am PT with SPARK experts Yannick Moy and Rod Chapman. Together, they will present the current status of the SPARK solution and explain how it can be successfully adopted in your current software development processes.
Judging for the first annual Make with Ada competition has come to an end and we can now reveal the results.
Customizing build target switches In the first post in this series (Integrate new tools in GPS) we saw how to create new build targets in GPS to spawn external tools via a menu or toolbar button, and then display the output of that tool in its own console, as well as show error messages in the Locations view.
One of the interesting aspects of developing software for a bare-board target is that displaying complex application-created information typically requires more than the target board can handle. Although some boards do have amazing graphics capabilities, in some cases you need to have the application on the target interact with applications on the host. This can be due to the existence of special applications that run only (or already) on the host, in particular.
If you’ve been looking for a way to start your next embedded project in Ada or SPARK. Then, look no further than the Make with Ada competition!
I recently started working on an Ada binding for the excellent libuv C library. This library provides a convenient API to perform asynchronous I/O under an event loop, which is a popular way to develop server stacks. A central part of this API is its enumeration type for error codes: most functions use it. Hence, one of the first things I had to do was to bind the enumeration type for error codes. Believe it or not: this is harder than it first seems!
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.
AdaCore provides several tools with certification and qualification capabilities, for the rail and avionics industry. Quentin Ochem’s presentation on “Certification and Qualification” at the 2015 AdaCore Tech Days in Boston, Massachusetts provided more information about these two standards, namely DO-178C and EN:50128:2011.
As seen in the previous blog article, AdaCore relies heavily on virtualisation to perform the testing of its GNAT Pro products for VxWorks.
We are pleased to announce that on April 27th our partner, Vector, will host a webinar to showcase their latest VectorCAST/Ada release!
AdaCore continues to build reliable and secure software for embedded software development tools. Last month, we attended Embedded World 2016, one of the largest conferences of its kind in Europe, to present our embedded solutions and our expertise for safety, and mission critical applications in a variety of domains.
Dr Carl Brandon of Vermont Technical College and his team of students used SPARK and Ada to successfully launch a satellite into space in 2013 and it has continued to orbit the Earth ever since! At our AdaCore Tech Days in Boston last year Dr Brandon explained further.
Just a few weeks ago, one of our partners reported a strange behavior of the well-known function Ada.Text_IO.Get_Line, which reads a line of text from an input file. When the last line of the file was of a specific length like 499 or 500 or 1000, and not terminated with a newline character, then Get_Line raised an exception End_Error instead of returning the expected string. That was puzzling for a central piece of code known to have worked for the past 10 years! But fair enough, there was indeed a bug in the interaction between subprograms in this code, in boundary cases having to do with the size of an intermediate buffer. My colleague Ed Schonberg who fixed the code of Get_Line had nonetheless the intuition that this particular event, finding such a bug in an otherwise trusted legacy piece of code, deserved a more in depth investigation to ensure no other bugs were hiding. So he challenged the SPARK team at AdaCore in checking the correctness of the patched version. He did well, as in the process we uncovered 3 more bugs.