nRF51: button long-press & short-multi press implement without BSP

In some case, it is ineviatable to use ONE button as multi-type signal source.Thus, in this post, I demonstate how to discern the state of button-pressed via nRF51 SDK. This article is an implementation of the function to support button long-pressed and multi-pressed as specified signal without BSP supplying.

the following article is a simple implement of:

1. long press with customized interval
2. short- multi press
3. the hurried pressings might lead system crash, it needs protection, so I ingore any-button signal in the next 4 seconds

BUTTON 1 implemented to measure the pressing time (in 0.1 sec)
BUTTON 2 implemented for  receiving double press


SDK 11/ nRF51822

*about how to start your UART, please read this article


STEP 1 . add ..\..\..\..\..\..\components\libraries\gpiote

add these two files to your project

STEP 2. add button definition
add the code about line 58.

#include "app_button.h"
#include "app_gpiote.h"
#define BUTTON_DEBOUNCE_DELAY   10 
#define APP_GPIOTE_MAX_USERS             1  . 

STEP 3. buttons initialization
change func buttons_leds_init( ) like this

static void buttons_leds_init(bool * p_erase_bonds)
{
    bsp_event_t startup_event;

    uint32_t err_code = bsp_init(BSP_INIT_NONE,
                                 APP_TIMER_TICKS(30, APP_TIMER_PRESCALER), 
                                 bsp_event_handler);
    APP_ERROR_CHECK(err_code);
    
 
    static app_button_cfg_t p_button[] = {{BUTTON_1, APP_BUTTON_ACTIVE_LOW, NRF_GPIO_PIN_PULLUP, button_handler},
                                          {BUTTON_2, APP_BUTTON_ACTIVE_LOW, NRF_GPIO_PIN_PULLUP, button_handler},};

                                        
    APP_GPIOTE_INIT(APP_GPIOTE_MAX_USERS);
                      
  // Initializing the buttons.
    err_code = app_button_init(p_button, sizeof(p_button) / sizeof(p_button[0]), BUTTON_DEBOUNCE_DELAY);
    APP_ERROR_CHECK(err_code);
                      
    err_code = app_button_enable();
    APP_ERROR_CHECK(err_code);     

    err_code = bsp_btn_ble_init(NULL, &startup_event);
    APP_ERROR_CHECK(err_code);
                      
    *p_erase_bonds = (startup_event == BSP_EVENT_CLEAR_BONDING_DATA);
}

add button_handler( ) above buttons_leds_init ( )

static void button_handler(uint8_t pin_no, uint8_t button_action)
{ 
 uint32_t err_code;
 
 if (false != is_able_to_receiving_button_pressed_signal)
 {
  if(button_action == APP_BUTTON_PUSH)
  {
   switch(pin_no)
   {
    case BUTTON_1:
     PRINTF_MSG("press button 1 \r\n");
                 
     err_code = app_timer_start(measure_pressed_time_timer_id,PRESS_MEASURE_INTERVAL, NULL);
     APP_ERROR_CHECK(err_code);
     break;
         
    case BUTTON_2:   
    if (0 == button2_press_count)
    {   
     err_code = app_timer_start(double_press_id,DOUBLE_PRESS_READ_INTERVAL, NULL);
     APP_ERROR_CHECK(err_code);
    }
     
     break;          
      
    default:
     break;
   }
  }
  else if (button_action == APP_BUTTON_RELEASE)
  {
   switch(pin_no)
   {
    case BUTTON_1:                 
    PRINTF_MSG("button 1 release\r\n"); 
    uint32_t err_code;
    err_code = app_timer_stop(measure_pressed_time_timer_id);
    APP_ERROR_CHECK(err_code);
   
    printf("**button1_measured_count= %f totally**\r\n",button1_measured_count*0.1); 
    button1_measured_count= 0;
   
    is_able_to_receiving_button_pressed_signal= false;
    
    app_timer_start(button_restrict_id,BUTTON_RESTRICT_INTERVAL, NULL);
    break;
       
    case BUTTON_2:
    //PRINTF_MSG("button 2 release\r\n");
    
    button2_press_count= button2_press_count+1;
     
   if (DOUBLE_PRESS == button2_press_count)
   {
    is_able_to_receiving_button_pressed_signal = false;
    printf("detect double press !!\r\n");
     
    app_timer_start(button_restrict_id,BUTTON_RESTRICT_INTERVAL, NULL);
         
   } 
                    
    break;
       
    case BUTTON_3:
    break;
    
   default:
    break;
   }
  }
 }
 
}

STEP 4.  create timers

add the code about line.120

static uint16_t button1_measured_count= 0;
APP_TIMER_DEF(measure_pressed_time_timer_id); 
#define PRESS_MEASURE_INTERVAL               APP_TIMER_TICKS(100, APP_TIMER_PRESCALER)

static uint8_t button2_press_count;
APP_TIMER_DEF(double_press_id);
#define DOUBLE_PRESS_READ_INTERVAL        APP_TIMER_TICKS(1500, APP_TIMER_PRESCALER)
#define DOUBLE_PRESS                     (0x02)

static bool is_able_to_receiving_button_pressed_signal= true;

APP_TIMER_DEF(button_restrict_id);
#define BUTTON_RESTRICT_INTERVAL          APP_TIMER_TICKS(4000, APP_TIMER_PRESCALER)

add the code in timer_init ( )

uint32_t err_code;
  
err_code = app_timer_create(&measure_pressed_time_timer_id,
                               APP_TIMER_MODE_REPEATED,
                                button1_triggered_event_handler);
                   
APP_ERROR_CHECK(err_code);
  
  
err_code = app_timer_create(&double_press_id,
                               APP_TIMER_MODE_SINGLE_SHOT,
                              button2_triggered_event_handler);
                   
APP_ERROR_CHECK(err_code);
    
err_code = app_timer_create(&button_restrict_id,
                               APP_TIMER_MODE_SINGLE_SHOT,
                               button_restrict_handler);
                   
APP_ERROR_CHECK(err_code);

about the variable"is_able_to_receiving_button_pressed_signal ":

once the variable is_able_to_receiving_button_pressed_signal becomes false, the button pressed would be ignore, it will prevent system from crash of busy interruption.


add the code above timer_init ( )

static void  button1_triggered_event_handler(void * p_context)
{
 UNUSED_PARAMETER(p_context);

 button1_measured_count++;
 printf("recent counter = %f\r\n",button1_measured_count*0.1);
}


static void button2_triggered_event_handler(void * p_context)
{
 UNUSED_PARAMETER(p_context);
 uint32_t err_code;
 

 printf("button2_press_count= %d\r\n",button2_press_count); 
 button2_press_count= 0; 
}

 
static void button_restrict_handler(void * p_context)
{
 UNUSED_PARAMETER(p_context);
 
 is_able_to_receiving_button_pressed_signal = true;
 
 printf("can received button\r\n");
}

program and upload to your device.


STEP 5.Test

I long press button 1 for 10 sec then rapidly press button 2
the device can count how long I press button 1 and only receive 2 press of button 2

like this:

Reference:
https://github.com/NordicSemiconductor/nrf51-app-button-example/blob/master/main.c

nRF51: A precise description of DFU_OTA

In this article will have 2 parts.
part 1 will describe how to make a DFU zip  file
part 2 will describe how to resolve "DFUtarg" after program bootloader.
(which means you don't need to press S4 button)

PART 1.

STEP 1. hex file in ./build folder.

this is  BLE advertisng name of my device

you can see it in mobile app

and I try to OTA the device and change its advertisng name.


























__________________________________________________________________________



I program again and change  DEVICE_NAME  to "nrf_agatha"
like this

find the .hex in
C:\..\pca10028\s130\arm5_no_packs\_build

STEP 2. install necessary application on PC
please install below applicaiton on your PC

nrf command line tool
https://www.nordicsemi.com/eng/Products/Bluetooth-low-energy/nRF51822

master control panel (MCP)
https://www.nordicsemi.com/eng/nordic/Products/nRF51-DK/nRF-MCP-x64/38907


STEP 3.command for making a zip file

copy this .hex file to
C:\Program Files (x86)\Nordic Semiconductor\Master Control Panel\3.10.0.14\nrf

open cmd.exe
and type the below command

cd C:\Program Files (x86)\Nordic Semiconductor\Master Control Panel\3.10.0.14\nrf
nrfutil.exe dfu genpkg --application nrf51422_xxac_s130.hex --application-version 0xffff --dev-revision 0xffff --dev-type 0xffff --sd-req 0xfffe nrf_agatha.zip

the result

and put nrf_agatha.zip to your mobile .


STEP 4.OTA upload test

start app nRF_Toolbox and press DFU

select .zip file

select device

start upload

disconnect

and you will the name change

PART 2. how to avoid "DFUtarg"
after programing

Softdevice  >
C:\..\nRF5x_SDK_11.0.0\components\softdevice\s130\hex

application >
(as your folder)

bootloader  >
C:\...\nRF5x_SDK_11.0.0\examples\dfu\bootloader\pca10028\dual_bank_ble_s130\arm5_no_packs\_build


go to
C:\Program Files (x86)\Nordic Semiconductor\nrf5x\bin

open cmd and type this command

cd C:\Program Files (x86)\Nordic Semiconductor\nrf5x\bin
nrfjprog.exe --family nrf51 --memwr 0x3fc00 --val 1

and type this

nrfjprog.exe --family nrf51 --reset

Note :
the above info had already write in my previous blogger, and this article just only for step-by-step