Chapter 2. API Reference
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// configSUPPORT_STATIC_ALLOCATION is set to 1. The PRIVILEGED_DATA macro can
// be used to force the variable into the RTOS kernel's privileged data area.
static PRIVILEGED_DATA StaticTask_t xTaskBuffer;
static const TaskParameters_t xCheckTaskParameters =
{
vATask, // pvTaskCode - the function that implements the task.
"ATask", // pcName - just a text name for the task to assist debugging.
100, // usStackDepth - the stack size DEFINED IN BYTES.
NULL, // pvParameters - passed into the task function as the function␣
,→parameters.
( 1UL | portPRIVILEGE_BIT ),// uxPriority - task priority, set the␣
,→portPRIVILEGE_BIT if the task should run in a privileged state.
cStackBuffer,// puxStackBuffer - the buffer to be used as the task stack.
// xRegions - Allocate up to three separate memory regions for access by
// the task, with appropriate access permissions. Different processors have
// different memory alignment requirements - refer to the FreeRTOS␣
,→documentation
// for full information.
{
// Base address Length Parameters
{ cReadWriteArray, 32, portMPU_REGION_READ_WRITE },
{ cReadOnlyArray, 32, portMPU_REGION_READ_ONLY },
{ cPrivilegedOnlyAccessArray, 128, portMPU_REGION_PRIVILEGED_READ_
,→WRITE }
}
&xTaskBuffer; // Holds the task's data structure.
};
int main( void )
{
TaskHandle_t xHandle;
// Create a task from the const structure defined above. The task handle
// is requested (the second parameter is not NULL) but in this case just for
// demonstration purposes as its not actually used.
xTaskCreateRestricted( &xRegTest1Parameters, &xHandle );
// Start the scheduler.
vTaskStartScheduler();
// Will only get here if there was insufficient memory to create the idle
// and/or timer task.
for( ;; );
}
Memory regions are assigned to a restricted task when the task is created by a call to xTaskCreateRestricted().
These regions can be redefined using vTaskAllocateMPURegions().
Example usage:
// Define an array of MemoryRegion_t structures that configures an MPU region
// allowing read/write access for 1024 bytes starting at the beginning of the
// ucOneKByte array. The other two of the maximum 3 definable regions are
// unused so set to zero.
static const MemoryRegion_t xAltRegions[ portNUM_CONFIGURABLE_REGIONS ] =
{
// Base address Length Parameters
{ ucOneKByte, 1024, portMPU_REGION_READ_WRITE },
{ 0, 0, 0 },
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