Anybody having knowledge on VRTX
I need to understand the internals of VRTX ( A RTOS). How is it different from other commercial/free RTOS? What makes VRTX unique in Embedded systems? ...
rtos
Embedded programming books
What embedded programming/design books would you suggest? With embedded I mean near to hardware programming in ASM and C/C++. I'm looking something related to best practices in embedded programming/design. Operation system could be Linux, Real Time Linux or any other RTOS. ...
why are RTOS coded only in c?
Is it necessary to code RTOS in C language always? Why can't that be coded in java or some other technology..?? Is that because of the absence of pointer concept in java? ...
open source RTOS code links
Where can I find open source c code for RTOS? ...
Interrupts and Timer in RTOS
Assume there is a interrupt based callback,The isr disable the interrupt and goes for a callback,then we start a timer.The timer disables all the interrupt in the system and then when it is stopped it enables them back.The question what is a need of disabling and enabling all the interrupts inside the timer functions?? also incase we use...
Code Composer 4 (Eclipse based)- makefiles
How do I prevent Code Composer 4 (which is based on Eclipse) from generating its own makefile and use the one I provide instead? Background: I am starting a FreeRTOS project on a MSP430F5436 using Code Composer 4 and have a demo app with a supplied make file) Thanks! ...
FreeRTOS configTICK_RATE_HZ problem
Hi, I am using an MSP430f5438 with version 5.4 of FreeRTOS. I am having a funny problem that I can't figure out. Basically, when I set configTICK_RATE_HZ to different values, the LED blinks faster or slower; it should stay the same rate. It blinks slower the higher i set configTICK_RATE_HZ, and faster when I set TICK_RATE lower. vTas...
Who schedules the scheduler in OS - Isn't it a chicken and egg scenario?
Who schedules the scheduler? Which is the first task created and how is this first task created? Isn't any resource or memory required for it? isn't like a chicken and egg scenario? Isn't scheduler a task? Does it get the CPU at the end of each time slice to check which task needs to be given CPU? Are there any good links which makes...
In vxworks, should every task be spawned with VX_FP_TASK option?
In vxworks, should every task be spawned with VX_FP_TASK option? The VX_FP_TASK option is required if your task uses any floating point operations. But how does one predict the future - i mean, how can one know if he/she will use float or not? While fixing any bug or introducing new code, should the programmer find which all tasks wil...
FreeRTOS Sleep Mode hazards while using MSP430f5438
Hi, I wrote an an idle hook shown here void vApplicationIdleHook( void ) { asm("nop"); P1OUT &= ~0x01;//go to sleep lights off! LPM3;// LPM Mode - remove to make debug a little easier... asm("nop"); } That should cause the LED to turn off, and MSP430 to go to sleep when there is nothing to do. I turn the LED on during...
Are there any lightweight analogues to CORBA/RPC for embedded programs?
I am writing embedded applications for different hardware (avr, arm7, tms55xx…) and different rtoses (freeRTOS, rtx, dsp/bios). And every second of them needs to communicate with PC or another digital device. Sometimes interactions logic is very advanced. So I'm interesting in common methodology (like state-machine programming style), pr...
Open source segmented interrupt architecture RTOS?
A segmented interrupt architecture RTOS can boast "zero interrupt latency" using clever partitioning of work between the interrupt handler and the scheduler. There are at least a couple proprietary closed source instances of this approach, e.g., AVIX and Quasarsoft- Q-Kernel. A related SO question asked about open source RTOS links, but...
single common address space for all tasks
Hi, How to give single common address space for all tasks. IF its happening like this can we avoid virtual to physical memory mapping. I f all task sharing common address space then how can we avoid virtual to physical memory mapping. ...
Design patterns commonly used for RTOS (VXworks)
Hi, Can anyone help me on design patterns commonly used for RTOS? In VXworks, which pattern is more preferable? ...
How to calculate a RTOS task's time
Hello all, I have written a code in c for Arm7 using RTOS. There are multiple tasks who's priority is set to same level. So the tasks executes on round-robin base. There is an exception that one task (Default) has set to lower priority then the other task in rtos. So that if no task is running, the default or lower priority task runs. ...
Has anyone evaluated NuttX RTOS?
While reading Linux User's Journal today, I stumbled across a little blurb about NuttX RTOS. I checked out their website and was fairly impressed with it's feature set and it's ability to put it in an 8052! I find it interesting that it supports POSIX which is something I have helped worked on for one of my clients in-house RTOS. This on...
Context switch time - Role of RTOS and Processor
Does the RTOS play a major role or processor play a major role in determining the time for context switch ? What is the percentage of share between these two major players in determining the context switch time . Can anyone tell with respect to uC/OS-II RTOS ? ...
Reduce resource usage of an Idle task
I find that in uC/OS-II RTOS, there is an idle task that gets executed when no other task is ready to run. If an idle task can consume resources, how can we reduce it ? ...
Lowest context switch time
Which processor has the best context switch time ? ...
Gang scheduling in RTOS over a multicore processor
I understand that Gang scheduling is a scheduling algorithm for parallel systems that schedules related threads or processes to run simultaneously on different processors. Gang scheduling is used so that if two or more threads or processes communicate with each other, they will all be ready to communicate at the same time. However, how...