Function esp_idf_svc::sys::xEventGroupClearBits

source ยท
pub unsafe extern "C" fn xEventGroupClearBits(
    xEventGroup: *mut EventGroupDef_t,
    uxBitsToClear: u32,
) -> u32
Expand description

Clear bits within an event group. This function cannot be called from an interrupt.

@param xEventGroup The event group in which the bits are to be cleared.

@param 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.

@return The value of the event group before the specified bits were cleared.

Example usage: @code{c} #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.
 }

} @endcode \ingroup EventGroup