main.cpp

00001 // For Arch and Xadow M0, use on-board button for normal input function rather than reset function
00002 // single click - LED1 on
00003 // double click - LED2 on
00004 // long click - LED1 and LED2 on, and then the board will restart
00005 //
00006 // Note: To enter ISP mode, press the button and then power on (power-on reset)
00007 
00008 #include "mbed.h"
00009 #include "pinmap.h"
00010 
00011 #define BUTTON_DOWN  0
00012 
00013 InterruptIn button(P0_1);       // on-board button of Arch or Xadow M0
00014 BusOut leds(LED1, LED2);
00015 
00016 uint8_t button_down_event = 0;
00017 
00018 void button_callback()
00019 {
00020     button_down_event = 1;      // set button down event flag
00021 }
00022 
00023 int button_detect()
00024 {
00025     int t = 0;
00026     
00027     while (1) {
00028         if (button.read() != BUTTON_DOWN) {
00029             if (t < 30) {
00030                 return 0;     // for anti shake
00031             } else {
00032                 break;
00033             }
00034         }
00035         
00036         if (t > 3000) {        // More than 3 seconds
00037             return -1;          // long click
00038         }
00039         
00040         t++;
00041         wait_ms(1);
00042     }
00043     
00044     if (t > 4000) {             // More than 0.4 seconds
00045         return 1;               // single click
00046     }
00047     
00048     while (true) {
00049         if (button.read() == BUTTON_DOWN) {
00050             wait_ms(1);
00051             if (button.read() == BUTTON_DOWN) {
00052                 return 2;      // double click
00053             }
00054             
00055             t += 10;
00056         }
00057         
00058         if (t > 400) {
00059             return 1;          // The interval of double click supposes to be less than 0.4 seconds, so it's single click
00060         }
00061         
00062         t++;
00063         wait_ms(1);
00064     }
00065 }
00066 
00067 
00068 int main() {
00069     // start 
00070     leds = 1;
00071     wait(0.2);
00072     leds = 3;
00073     wait(0.2);
00074     leds = 2;
00075     wait(0.2);
00076     leds = 0;
00077     
00078     pin_function(P0_0, 1);      // use RESET pin as 
00079     button.fall(button_callback);
00080     
00081     while(1) {
00082         if (button_down_event != 0) {
00083             int clicks = button_detect();
00084             if (clicks == 1) {
00085                 leds = 0x01;
00086             } else if (clicks == 2) {
00087                 leds = 0x02;
00088             } else if (clicks == -1) {  // long press
00089                 leds = 0x03;
00090                 while (button.read() == BUTTON_DOWN) { } // wait until button is released. note: remove this line to boot into ISP mode after reset
00091                 NVIC_SystemReset();                      // reset
00092             }
00093             
00094             wait(1);
00095             leds = 0;
00096             
00097             button_down_event = 0;      // clear button down event flag
00098         }
00099         
00100         // sleep();
00101         // or do something else
00102     }
00103 }