Chapter 2. API Reference
Clear bits within an event group. This function cannot be called from an interrupt.
Example usage:
#define BIT_0 ( 1 << 0 )
#define BIT_4 ( 1 << 4 )
void aFunction( EventGroupHandle_t xEventGroup )
{
EventBits_t uxBits;
// Clear bit 0 and bit 4 in xEventGroup.
uxBits = xEventGroupClearBits(
xEventGroup, // The event group being updated.
BIT_0 | BIT_4 );// The bits being cleared.
if( ( uxBits & ( BIT_0 | BIT_4 ) ) == ( BIT_0 | BIT_4 ) )
{
// Both bit 0 and bit 4 were set before xEventGroupClearBits() was
// called. Both will now be clear (not set).
}
else if( ( uxBits & BIT_0 ) != 0 )
{
// Bit 0 was set before xEventGroupClearBits() was called. It will
// now be clear.
}
else if( ( uxBits & BIT_4 ) != 0 )
{
// Bit 4 was set before xEventGroupClearBits() was called. It will
// now be clear.
}
else
{
// Neither bit 0 nor bit 4 were set in the first place.
}
}
Return The value of the event group before the specified bits were cleared.
Parameters
• xEventGroup: The event group in which the bits are to be cleared.
• uxBitsToClear: A bitwise value that indicates the bit or bits to clear in the event group. For
example, to clear bit 3 only, set uxBitsToClear to 0x08. To clear bit 3 and bit 0 set uxBitsToClear
to 0x09.
EventBits_t xEventGroupSetBits(EventGroupHandle_t xEventGroup, const EventBits_t uxBitsToSet)
Set bits within an event group. This function cannot be called from an interrupt. xEventGroupSetBits-
FromISR() is a version that can be called from an interrupt.
Setting bits in an event group will automatically unblock tasks that are blocked waiting for the bits.
Example usage:
#define BIT_0 ( 1 << 0 )
#define BIT_4 ( 1 << 4 )
void aFunction( EventGroupHandle_t xEventGroup )
{
EventBits_t uxBits;
// Set bit 0 and bit 4 in xEventGroup.
uxBits = xEventGroupSetBits(
xEventGroup, // The event group being updated.
BIT_0 | BIT_4 );// The bits being set.
(continues on next page)
Espressif Systems 934
Submit Document Feedback
Release v4.4
To Next Page
Loading...