Asparagus Official

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

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?

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?

Asparagus is a hardy perennial, meaning it can produce harvestable spears for 15 to 30 years once a bed is established.

Asparagus is a nutrient-dense "superfood," offering high fiber and vitamins with very few calories. How Do I Grow Asparagus? | Planting & Harvesting Guide

While green is most common, you can also find white asparagus (grown in the dark to prevent photosynthesis) and purple asparagus . Nutritional and Health Benefits

Asparagus ( Asparagus officinalis ) is often hailed as the "king of vegetables," signaling the true arrival of spring with its elegant, spear-like shoots. A member of the lily family, it is related to onions, garlic, and leeks, and has been cultivated for over 2,500 years for both its unique flavor and medicinal properties. Growth and Cultivation

Asparagus is dioecious, with separate male and female plants. Male plants are generally preferred by growers because they live longer, emerge earlier, and don't expend energy producing the small, red (and toxic) berries found on female plants.

It typically takes about three seasons after planting for a crown to reach full maturity for a complete harvest.

The plant grows from an underground root system known as a "crown".

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.