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Questions tagged [ucos]

µC/OS is a low-cost priority-based pre-emptive real-time multitasking operating system kernel for microprocessors, written mainly in the C programming language. It is intended for use in embedded systems. It is a scalable, ROMable, pre-emptive kernel that manages a number of tasks. It allows for unlimited tasks, semaphores, mutexes, event flags, message queues, timers and memory partitions. The user allocates all kernel objects at run time.

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How to install uCos on arm9 [ mini2440 ]

I'm very new to embedded programming, and my first project is installing uCos on mini2440 [arm9] . Are there any tutorials for beginner like me to install uCos on arm9 ? Thanks first :)
Dzung Nguyen
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Memory allocation under uCOS-III

I'm developing a C-library to be used under uCOS-III. The CPU is an ARM Cortex M4 SAM4C. Within the library I want to use a third party product X, whose particular name is not relevant here. The source code for X is completely available and compiles…
MichaelW
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What are the Parameters on which RTOS are compared?

I want to compare two RTOS (e.g. -> Keil-RTX ,Ucos-iii and freertos), but I do not know on what parameters I need to compare them for e.g. Memory footprint, certified etc. On which points do we compare RTOS ?
G.ONE
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Semaphore under uCOS-III

I use uCOS-III under Arm Cortex M4 and have the following problem: If OSSemPend() is executed twice within the same task), like timeout = 100; /* 0.1 s */ OSSemPend(rtos_sem_p, timeout, OS_OPT_PEND_BLOCKING, NULL, &err); ... OSSemPend(rtos_sem_p,…
MichaelW
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Execute a code only one time in C

I want execute a code only one time. I used a solution based on a global varibale of bool type. My question, is it the best solution? Remark: I use ucos-II. if (TRUE == Lock) { /*Code to execute one time*/ } /*The reste of the code*/
Stack Over
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uCOS-ii mutex vs critical section vs scheduler locking vs semaphore

I'm writing for an embedded system running uCOS-ii. I need to atomically write (and read) two integers (value and timestamp which should be synchronized with one another). The easiest way is to wrap the writing of the two values with a critical…
Dina
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uC/OS-II How to dynamically load a task

Basically, when my system is running, I would like the user to ftp some new code to the SD card, and dynamically load the new function and create a task to run in the system. This is normal for Linux. For example, I can compile a SO, and…
Hai Bi
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creating task inside other task in freertos

I am an RTOS newbie and I am creating a simple real time system for automotive I am wondering if it possible to create a task inside another task. I tried to do this by the following method but it doesn't work. void vTask1 {…
Jay Shenawy
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having linker error developing in c++ using IAR and Renesas rx62n and Ucos III

I purchased Michael Barr's embedded bootcamp training. It includes an IAR project that have all libraries configured. This project file is what all projects are created from. The code in project file are in c. I would like to develop in c++. There…
Patrick Glenn
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Application crashes when debugging over jtag

I'm having an issue when attempting to analyze variables in the Eclipse IDE, while in debug mode. At a breakpoint, I'll try to expand a data structure, in the Eclipse variables window, however, the member doesn't display and the program running on…
dsell002
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uC/OS-II Will OS_EXIT_CRITICAL() execute in the OS_Sched()?

In the OS_Sched(), a context switch will perform after OS_TASK_SW(), processor will execute a higher priority task. But when will the OS_EXIT_CRITICAL() be executed? void OS_Sched (void) { #if OS_CRITICAL_METHOD == 3u /*…
Zhuxian
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Finishing uC/OS-II

For future developers' sake and to seek a better code organization and structure, I need to finish micrium execution and go back to a bare-metal state. So, how can I pass the OSStart() point? Bellow, there's some minimal/pseudo code. while…
Jonny Quest
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Who can tell me that how could it get the value of register DS

In the source of uc/os, I couldn't understand the following code. *stk = _DS; It's comments is to get current value of DS. Can you tell me why?
nobody
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Print OSTime in UC/OS-II

Device : F28335 contorolCRAD and Experimenter's Kit - Delfino F28335. Ported ucos-II. I use OSTimeGet() function to get OSTime. But task1 returns '0' everytime and task2 doesn't work. What is the problem? How to fix this? App_Task1's priority =…
Jinho
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On the cortex-m3 platform, why does UCOS-III not use SVC to perform pendsv?

Recently, I am reading the source code of UCOS-III, and I have an question about UCOS-III's task switching when it running on the Cortex-M3 platform. It use PendSV for task switching by directly writing register SCB_ICSR(Interrupt control and state…
zhanglianpin
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