Quality RTOS & Embedded Software

download grave the fireflies 1988 720p blu ray hindi english japanese esubs vegamovies mkv portable
 Real time embedded FreeRTOS RSS feed 
Quick Start Supported MCUs PDF Books Trace Tools Ecosystem


Loading

FreeRTOS tasks can interrupt USB stack implementation?

Posted by ddudas on September 24, 2015

Hi all,

I'm using ST's CubeMX implementation on a F4 discovery board. I use ST's USB middlewares with FreeRTOS.

When I get a special OutputReport from PC side I have to answer nearly immediately (in 10-15 ms). Currently I cannot achieve this timing and it seems my high priority tasks can interrupt the USB callback. What do you think, is it possible? Because it's generated code I'm not sure but can I increase the priority of the USB interrupt (if there is any)?

Thank you, David


FreeRTOS tasks can interrupt USB stack implementation?

Posted by rtel on September 24, 2015

10 to 15 ms is very slow, so I'm sure its possible.

Where is the USB callback function called from? If it is an interrupt then it cannot be interrupted by high priority RTOS tasks. Any non interrupt code (whether you are using an RTOS or not) can only run if no interrupts are running.

Without knowing the control flow in your application its hard to know what to suggest. How is the OutputReport communicated to you? By an interrupt, a message from another task, or some other way?


FreeRTOS tasks can interrupt USB stack implementation?

Posted by ddudas on September 24, 2015

The callback which receive the data from PC is called from the OTGFSIRQHandler (it's the part of the HALPCDIRQHandler function). I think the problem is SysTickHandler's priority is higher than OTGFSIRQHandler and it's cannot be modified, but the scheduler shouldn't interrupt the OTGFSIRQHandler with any task handled by the scheduler. Am I wrong that the scheduler can interrupt the OTGFS_IRQHandler?


FreeRTOS tasks can interrupt USB stack implementation?

Posted by rtel on September 24, 2015

Download Grave The Fireflies 1988 720p Blu Ray Hindi English Japanese Esubs Vegamovies Mkv Portable Apr 2026

One afternoon an elderly woman joined their shelter. She moved with the deliberation of someone who had learned the geography of ruin. Her name was Hana, and she spoke in stories that smelled of soy and wood smoke. She showed them how to dry thin slices of radish and taught Taro to whittle spoons from the driftwood of a fallen roof beam. She did not offer false promises; instead, she taught them useful things: how to read the wind, where nettles hid beneath glossy leaves, which herbs calmed an aching belly.

Days thinned into a long, weathered record—meals became memory, paths became habit. Taro discovered that people could be kind and cruel in the same breath. A pair of soldiers passed with pockets full of biscuits; another pair demanded the kettle and left them only with a cudgel of silence. Once, outside the shelter, Mei found a field where fireflies blinked like a scattered prayer. She ran into the grass and laughed, her voice thin as reeds. She cupped a single insect in her hands and offered it to Taro: Look, she said, we found our lantern. One afternoon an elderly woman joined their shelter

The promise of green finally arrived with a spring that cracked the ash. Wild shoots came up between the cobbles and a young family returned to put a washing line between two blackened posts. The town rebuilt slowly, as if it had forgotten the exact shape of things and was relearning them by touch. The map in their mother’s tin had begun to fray at the edges; someone must have borrowed it because the tin held now only a small stack of letters—messages that never found their way home. She showed them how to dry thin slices

I can, however, write an original story inspired by Grave of the Fireflies’ themes (loss, sibling bond, wartime hardship) in a respectful, non-infringing way. Here’s a short story: Taro discovered that people could be kind and

And on nights when the city’s lights wavered with storms, a child would find the old brass lantern in a cupboard, blow the dust away, and ask to hear the story again. Mei would lift it into her hands, feel the weight of the past like a comforting warmth, and set it on the table. She would light the wick and for a moment the room would fill with the soft, steady pulse of a single, faithful flame.

When it felt safe enough, a relief train came through, its whistle a clean blade across the morning. People boarded with packs of belongings and faces made of different maps; others stayed, too weary to choose. Taro and Mei watched the train’s windows shine like eyes and thought of all the places they might go. They could hear, somewhere beyond the station, the hush of rebuilding—the slow, ordinary work of making a life out of leftover shadows.

Before they left, Taro filled the lantern with oil from a bottle a merchant traded for two carved spoons. He polished the glass until the brass reflected the sky. On the last night in the hollow, they set it beside their sleeping mat and lit the wick. The flame was small and trembled like a child learning to stand. For a while they simply watched: the light quivered, threw soft gold over Mei’s hair, and made Taro look like someone he had been before things broke.


FreeRTOS tasks can interrupt USB stack implementation?

Posted by ddudas on September 24, 2015

Thank you for the answer, I think I'm a bit confused with the Cortex ISR priorities :-) What I can observe is if I use a much higher osDelay in my high priority task I can respond for the received USB message much faster. This is why I think tasks can mess up with my OTG interrupt.




Copyright (C) Amazon Web Services, Inc. or its affiliates. All rights reserved.

Latest News

NXP tweet showing LPC5500 (ARMv8-M Cortex-M33) running FreeRTOS.

Meet Richard Barry and learn about running FreeRTOS on RISC-V at FOSDEM 2019

Version 10.1.1 of the FreeRTOS kernel is available for immediate download. MIT licensed.

View a recording of the "OTA Update Security and Reliability" webinar, presented by TI and AWS.


Careers

FreeRTOS and other embedded software careers at AWS.



FreeRTOS Partners

ARM Connected RTOS partner for all ARM microcontroller cores

Espressif ESP32

IAR Partner

Microchip Premier RTOS Partner

RTOS partner of NXP for all NXP ARM microcontrollers

Renesas

STMicro RTOS partner supporting ARM7, ARM Cortex-M3, ARM Cortex-M4 and ARM Cortex-M0

Texas Instruments MCU Developer Network RTOS partner for ARM and MSP430 microcontrollers

OpenRTOS and SafeRTOS

Xilinx Microblaze and Zynq partner