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Archive for the ‘RTOS’ Category

What was your first Arduino program? Probably an LED blinker — that seems to be the “hello world” of microcontrolllers. You probably moved on to things a little more complicated pretty quickly. At some point, things get harder because the Arduino lacks an operating system.

There are operating systems that will run on the Arduino. They aren’t full-featured like Windows or Linux, but they allow you to run multiple tasks that are both isolated from each other (to some degree) and have a way to cooperate (that is, synchronize, share data and resources, and so on). One such operating system is ChibiOS. It will run on AVR- and ARM-based devices. You can find documentation about the entire project on the home page along with other ports.

The problem with adopting a new operating system is always getting started. [ItKindaWorks] has started a video series on using ChibiOS and has posted three installments so far (see below; one is about getting started, the other two cover messaging, mutexes, and priorities).

If you want to follow along with the videos, the code is available on GitHub. We aren’t sure if he’s planning more videos, but these will be more than enough to get you started.

According to the ChibiOS project, they are better than many common similar operating systems because of their static design (you can put the processor to sleep without causing problems). They also support true threads instead of simple tasks, meaning that you can dynamically create and destroy threads and synchronize threads easily.

If you are building sophisticated software that needs multiple things occurring at once, having an operating system can make life a lot easier. We’ve seen examples of using ChibiOS ranging from motor control to MIDI players. There are quite a few choices other than ChibiOS, too, if you look around.


Filed under: Arduino Hacks

We live in a connected world, but that world ends not far beyond the outermost cell phone tower. [John Grant] wants to be connected everywhere, even in regions where no mobile network is available, so he is building a solar powered, handheld satellite messenger: The MyComm – his entry for the Hackaday Prize.

The MyComm is a handheld touch-screen device, much like a smartphone, that connects to the Iridium satellite network to send and receive text messages. At the heart of his build, [John] uses a RockBLOCK Mk2 Iridium SatComm Module hooked up to a Teensy 3.1. The firmware is built upon a FreeRTOS port for proper task management. [John] crafted an intuitive GUI that includes an on-screen keyboard to write, send and receive messages. A micro SD card stores all messages and contact list entries. Eventually, the system will be equipped with a solar cell, charging regulator and LiPo battery for worldwide, unconditional connectivity.

2016 will be an interesting year for the Iridium network since the first satellites for the improved (and backward-compatible) “Iridium NEXT” network are expected to launch soon. At times the 66 Iridium satellites currently covering the entire globe were considered a $5B heap of space junk due to deficiencies in reliability and security. Yet, it’s still there, with maker-friendly modems being available at $250 and pay-per-use rates of about 7 ct/kB (free downstream for SDR-Hackers). Enjoy the video of [John] explaining the MyComm user interface:

The HackadayPrize2016 is Sponsored by:

Filed under: Arduino Hacks, Cellphone Hacks, The Hackaday Prize

The Linux Foundation is a non-profit organization that sponsors the work of Linus Torvalds. Supporting companies include HP, IBM, Intel, and a host of other large corporations. The foundation hosts several Linux-related projects. This month they announced Zephyr, an RTOS aimed at the Internet of Things.

The project stresses modularity, security, and the smallest possible footprint. Initial support includes:

  • Arduino 101
  • Arduino Due
  • Intel Galileo Gen 2
  • NXP FRDM-K64F Freedom

The project (hosted on its own Website) has downloads for the kernel and documentation. Unlike a “normal” Linux kernel, Zephyr builds the kernel with your code to create a monolithic image that runs in a single shared address space. The build system allows you to select what features you want and exclude those you don’t. You can also customize resource utilization of what you do include, and you define resources at compile time.

By default, there is minimal run-time error checking to keep the executable lean. However, there is an optional error-checking infrastructure you can include for debugging.

The API contains the things you expect from an RTOS like fibers (lightweight non-preemptive threads), tasks (preemptively scheduled), semaphores, mutexes, and plenty of messaging primitives. Also, there are common I/O calls for PWM, UARTs, general I/O, and more. The API is consistent across all platforms.

You can find out more about Zephyr in the video below. We’ve seen RTOS systems before, of course. There’s even some for robots. However, having a Linux-heritage RTOS that can target small boards like an Arduino Due and a Freedom board could be a real game changer for sophisticated projects that need an RTOS.


Filed under: Arduino Hacks, ARM, linux hacks, news
Apr
18

Energia Multitasking uses RTOS on MSP432

arduino hacks, ARM, Cortex M4F, energia, IDE, launchpad, msp432, multitasking, RTOS Commenti disabilitati su Energia Multitasking uses RTOS on MSP432 

We keep wondering where the Arduino world is headed with the hardware getting more and more powerful. If the IDE doesn’t keep up what’s the point? Now we have at least one answer to that problem. Energia is the Arduino-like-framework for Texas Instruments based boards. They just came out with a multitasking system built into Energia targeted at the ARM Cortex-M4F based MSP432 Launchpad which we covered a few weeks back.

The announcement post gives a couple of examples of uses for multitasking. The simplest is blinking LEDs at different rates. If you wanted to do this closer to the metal you’re talking about multiple timers, or multiple compares on a single timer, perhaps a interrupt-driven-system-tick that has a high enough resolution for a wide range of your blinking needs. But these are not always easy to set up unless you are intimately comfortable with this particular architecture. The Energia multitasking will handle this for you. It’s upon the TI Real Time Operating System (TI-RTOS) but wraped in the familiar IDE.

The UI divorces you from thinking about the hardware at all. You simply launch a new tab and start coding as if you’re using a completely separate piece of hardware. The announcement post linked above mentions that these Sketches are running “in parallel”. Well… we know it’s not a multi-core system like the Propeller but we’ll let it slide. It is certainly easier than building your own scheduler for this type of hardware.

[Thanks MycoWx]


Filed under: Arduino Hacks, ARM
Dic
06

The 86Duino Zero Runs Linux on x86

86Duino, 86Duino Zero, arduino, ethernet, i2c, ipc, Linux, microSD, PCIE, RTOS, SPI, Vortex86EX, x86, xISA Commenti disabilitati su The 86Duino Zero Runs Linux on x86 

86Duino_ZERO-45D

DM&P has been producing low-power, x86-based Vortex processors for the embedded market for over ten years. Now in a nod to the Arduino market they have released the 86Duino Zero, a low-cost Arduino Leonardo sized board powered by their latest 300 MHz SoC Vortex86EX Processor.

This is a fully static 32-bit x86 processor board compatible with Windows OS, Linux and most other popular 32-bit RTOS. It integrates a PCIE bus, DDR3, ROM controller, xISA, I2C, SPI, IPC (Internal Peripheral Controllers with DMA and interrupt timer/counter included). The 86Duino Zero’s ports include USB 2.0 host and device coastline ports, a 10/100 Ethernet port and a microSD slot on the bottom of the board. The Zero’s baseboard also provides a 7-12V power jack, a reset button and a PCIe expansion connector.

The Zero supplies 14 digital I/O pins, half of which can provide 32-bit resolution PWM outputs and six 11-bit analog input pins. Each standard I/O pin supplies 16 mA while the 3.3 V pins can supply up to 400 mA. Like the Intel Galileo development board announced several weeks ago the 86Duino Zero marries Intel architecture to the Arduino platform. Its $39 price tag makes it an attractive proposition. [via]

The 86Duino Zero Runs Linux on x86 - [Link]



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