1 /**************************************************************************//**
2  * @file
3  * @brief Interrupt enable/disable unit API
4  * @author Energy Micro AS
5  * @version 3.0.0
6  ******************************************************************************
7  * @section License
8  * <b>(C) Copyright 2012 Energy Micro AS, http://www.energymicro.com</b>
9  *******************************************************************************
10  *
11  * Permission is granted to anyone to use this software for any purpose,
12  * including commercial applications, and to alter it and redistribute it
13  * freely, subject to the following restrictions:
14  *
15  * 1. The origin of this software must not be misrepresented; you must not
16  *    claim that you wrote the original software.
17  * 2. Altered source versions must be plainly marked as such, and must not be
18  *    misrepresented as being the original software.
19  * 3. This notice may not be removed or altered from any source distribution.
20  *
21  * DISCLAIMER OF WARRANTY/LIMITATION OF REMEDIES: Energy Micro AS has no
22  * obligation to support this Software. Energy Micro AS is providing the
23  * Software "AS IS", with no express or implied warranties of any kind,
24  * including, but not limited to, any implied warranties of merchantability
25  * or fitness for any particular purpose or warranties against infringement
26  * of any proprietary rights of a third party.
27  *
28  * Energy Micro AS will not be liable for any consequential, incidental, or
29  * special damages, or any other relief, or for any claim by any third party,
30  * arising from your use of this Software.
31  *
32  *****************************************************************************/
33 #include <stdint.h>
34 #include "em_int.h"
35 
36 /***************************************************************************//**
37  * @addtogroup EM_Library
38  * @{
39  ******************************************************************************/
40 
41 /***************************************************************************//**
42  * @addtogroup INT
43  * @brief Safe nesting interrupt disable/enable API
44  * @details
45  *  This module contains functions to safely disable and enable interrupts
46  *  at cpu level. INT_Disable() disables interrupts and increments a lock
47  *  level counter. INT_Enable() decrements the lock level counter and enable
48  *  interrupts if the counter was decremented to zero.
49  *
50  *  These functions would normally be used to secure critical regions.
51  *
52  *  These functions should also be used inside interrupt handlers:
53  *  @verbatim
54  *  void SysTick_Handler(void)
55  *  {
56  *    INT_Disable();
57  *      .
58  *      .
59  *      .
60  *    INT_Enable();
61  *  }
62  * @endverbatim
63  ******************************************************************************/
64 
65 /** Interrupt lock level counter. Set to zero initially as we normally enter
66  * main with interrupts enabled  */
67 uint32_t INT_LockCnt = 0;
68 
69 
70 /** @} (end addtogroup INT) */
71 /** @} (end addtogroup EM_Library) */
72