[nRF51822] 5、 霸屏了——详解nRF51 SDK中的GPIOTE（从GPIO电平变化到产生中断事件的流程详解）

1 // Macro to initialize GPIOTE module and reserving necessary memory for each of user.
2 APP_GPIOTE_INIT(MAX_USERS);

 1 // GPIOTE user identifier for the example module.
 2 static app_gpiote_user_id_t   m_example_user_id;// GPIOTE event handler.
 3 static void example_gpiote_event_handler(uint32_t event_pins_low_to_high, uint32_t event_pins_high_to_low);
 4 .
 5 .
 6 .
 7 uint32_t  low_to_high_bitmask = 0x0000000F; // Bitmask to be notified of transition from low to high for GPIO 0-3
 8 uint32_t  high_to_low_bitmask = 0x0000000E; // Bitmask to be notified of transition from high to low for GPIO 0-2
 9 uint32_t retval;retval = app_gpiote_user_register(&m_example_user_id,
10                                                   low_to_high_bitmask,
11                                                   high_to_low_bitmask, 
12                                                   example_gpiote_event_handler);
13                                                    
14 if (retval != NRF_SUCCESS){    
15     // Failed to register with user with GPIO module!
16 }
17 
18 .
19 .
20 .

 1 // GPIOTE event handler.
 2 void example_gpiote_event_handler (uint32_t event_pins_low_to_high, uint32_t event_pins_high_to_low)
 3 {    
 4     .    
 5     .    
 6     .    
 7     if (event_pins_low_to_high & 0x00000001)    
 8     {        
 9         // GPIO pin 0 transitioned from low to high.         
10         // Take necessary action.    
11     }    
12     if (event_pins_high_to_low & 0x00000004)    
13     {         
14         // GPIO pin 2 transitioned from high to low.         
15         // Take necessary action.    
16     } 
17     
18     .    
19     .    
20     .
21 }

 1 uint32_t retval;
 2 
 3 // Enable notifications for example user module which is already registered.
 4 retval = app_gpiote_user_disable(m_example_user_id);
 5 if (retval != NRF_SUCCESS)
 6 {    
 7     // Enabling notifications failed. Take corrective/needed action.    
 8     .
 9     .
10 } 
11 
12  . 
13  . 
14  .
15 // Enable notifications for example user module which is already registered.
16 retval = app_gpiote_user_enable(m_example_user_id);
17 if (retval != NRF_SUCCESS)
18 {    
19     // Enabling notifications failed. Take corrective/needed action.    
20     .    
21     .
22 }

 1 uint32_t retval;
 2 uint32_t gpio_pin_state;
 3 
 4 retval = app_gpiote_pins_state_get(m_example_user_id,&gpio_pin_state);
 5 if (retval != NRF_SUCCESS)
 6 {    
 7     // Failed to read state information. Take corrective action.
 8 }else{
 9     .    
10     .    
11     if (gpio_pins_state & 0x00000006) // Checks if pin one and two are set    
12     {        
13         // Take necessary action    
14     }    
15     .    
16     .
17 }