PIC24 Support Libraries
 All Data Structures Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
int0_wakeup.c
Go to the documentation of this file.
1 /*
2  * "Copyright (c) 2008 Robert B. Reese, Bryan A. Jones, J. W. Bruce ("AUTHORS")"
3  * All rights reserved.
4  * (R. Reese, reese_AT_ece.msstate.edu, Mississippi State University)
5  * (B. A. Jones, bjones_AT_ece.msstate.edu, Mississippi State University)
6  * (J. W. Bruce, jwbruce_AT_ece.msstate.edu, Mississippi State University)
7  *
8  * Permission to use, copy, modify, and distribute this software and its
9  * documentation for any purpose, without fee, and without written agreement is
10  * hereby granted, provided that the above copyright notice, the following
11  * two paragraphs and the authors appear in all copies of this software.
12  *
13  * IN NO EVENT SHALL THE "AUTHORS" BE LIABLE TO ANY PARTY FOR
14  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT
15  * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE "AUTHORS"
16  * HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
17  *
18  * THE "AUTHORS" SPECIFICALLY DISCLAIMS ANY WARRANTIES,
19  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
20  * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
21  * ON AN "AS IS" BASIS, AND THE "AUTHORS" HAS NO OBLIGATION TO
22  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS."
23  *
24  * Please maintain this header in its entirety when copying/modifying
25  * these files.
26  *
27  *
28  */
29 
30 #include "pic24_all.h"
31 
32 /** \file
33  * Demonstrates the use of int0 interrupt
34  * to wake from Sleep mode.
35  * Pushbutton on an int0 pin is used to wake from Sleep mode.
36  *
37  *
38  */
39 
40 /// Interrupt Service Routine for INT0
41 void _ISRFAST _INT0Interrupt (void) {
42  _INT0IF = 0; //clear the interrupt bit
43 }
44 
45 /// Switch1 configuration, RB7 shares INT0 pin on PIC24HGP202
46 inline void CONFIG_SW1() {
47  CONFIG_RB7_AS_DIG_INPUT(); //use RB7 for switch input
48  ENABLE_RB7_PULLUP(); //enable the pullup
49 }
50 
51 int main (void) {
52  configBasic(HELLO_MSG);
53  /** Configure the switch ***********/
54  CONFIG_SW1(); //enables individual CN interrupt also
55  /** Configure INT0 interrupt */
56  _INT0IF = 0; //Clear the interrupt flag
57  _INT0IP = 2; //Choose a priority
58  _INT0EP = 1; //negative edge triggerred
59  _INT0IE = 1; //enable INT0 interrupt
60  while (1) {
61  outString("Entering Sleep mode, press button to wake.\n");
62  // Finish sending characters before sleeping
64  SLEEP(); //macro for asm("pwrsav #0")
65  }
66 }