PIC32MZ Time delay interference using FreeRTOS

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1

I have written a function below which helps generate a time delay in micro-seconds. i plan to set time delays in the rage of 2-5 micro-seconds.
void Delay_Us(unsigned int Us)
{

// Convert microseconds us into how many clock ticks it will take
Us *=(SYS_CLK_FREQ / 1000000) / 2; // Core Timer updates every 2 ticks

_CP0_SET_COUNT(0); // Set Core Timer count to 0

// Wait until Core Timer count reaches the number we calculated
while (Us > _CP0_GET_COUNT());
}
I have FREERTOS configured in the code. I am wondering how the function defined will affect its total time duration if FreeRTOS functions vTaskStartScheduler() and xTaskCreate are executed independently during the small interval.
Specifications:

Compiler: XC32,
IDE: MPLAB X IDE v4.05
Chip: PIC32MZ2048EFG144

I would appreciate some guidance.

Thank you,
Kenny

2

I’m not sure how calling vTaskStartScheduler() could effect it because if that function has not been called then there will be no multithreading and calling Delay_Us will result in the processor sitting in Delay_Us until the delay is complete. In other words if the scheduler has not been started then FreeRTOS cannot impact the function.

After the scheduler has been started is a different matter because any task calling Delay_Us can get preempted by any higher priority task, and therefore Delay_Us will not be accurate - the delay time achieved will be either the desired microsecond delay if no context switches occur, or an unknown time if context switches do occur.

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