How LED ON at same time in Central connected to 3 ble peripheral.

RE: How LED ON at same time in Central connected to 3 ble peripheral.

Susheel Nuguru — Mon, 24 Sep 2018 12:27:02 GMT

Hi Parag, Sorry for late reply.

not sure what was unclear in my previous answer. Can you please ask more specific questions.

RE: How LED ON at same time in Central connected to 3 ble peripheral.

Samarth — Tue, 11 Sep 2018 18:33:41 GMT

Not understand what you are saying, will you please explain little bit more with example.

Thanks.....!!!

RE: How LED ON at same time in Central connected to 3 ble peripheral.

Susheel Nuguru — Tue, 11 Sep 2018 04:55:33 GMT

Hi Parag, Sorry for the late reply

For every connection with your slave you will get different conn_handle value.

So when the connection is established you need to save them into m_conn_handle1, m_conn_handle2 and m_conn_handle3

In your button event, you compare the conn_handle with one of these to know which device is sending this button events and light the appropriate LED

RE: How LED ON at same time in Central connected to 3 ble peripheral.

Samarth — Mon, 03 Sep 2018 19:06:05 GMT

It's Ok Aryan,

Now i have solved this issue by defining bas event in init function my mistake i forgot to initialize Now our battery update code is well working.

But now problem is we have 3 BLE peripherals so for that we want to use only one program all of these three devices. And at central side want to glow particular led with slave only.

For that slave 1 i use this function:

static void button_event_handler(uint8_t pin_no, uint8_t button_action)
{
    ret_code_t err_code;

    switch (pin_no)
    {
        case LEDBUTTON_BUTTON1:
            NRF_LOG_INFO("Send first button state change.");
 //           err_code = ble_lbs_on_button_change(m_conn_handle, &m_lbs, button_action);
      err_code = button_action ? ble_lbs_on_button_change(m_conn_handle, &m_lbs, 1) : ble_lbs_on_button_change(m_conn_handle, &m_lbs, 0);
            if (err_code != NRF_SUCCESS &&
                err_code != BLE_ERROR_INVALID_CONN_HANDLE &&
                err_code != NRF_ERROR_INVALID_STATE &&
                err_code != BLE_ERROR_GATTS_SYS_ATTR_MISSING)
            {
                APP_ERROR_CHECK(err_code);
            }
            break;
        case LEDBUTTON_BUTTON2:
            NRF_LOG_INFO("Send second button state change.");
 //           err_code = ble_lbs_on_button_change(m_conn_handle, &m_lbs, button_action);
     err_code = button_action ? ble_lbs_on_button_change(m_conn_handle, &m_lbs, 3) : ble_lbs_on_button_change(m_conn_handle, &m_lbs, 2);
            if (err_code != NRF_SUCCESS &&
                err_code != BLE_ERROR_INVALID_CONN_HANDLE &&
                err_code != NRF_ERROR_INVALID_STATE &&
                err_code != BLE_ERROR_GATTS_SYS_ATTR_MISSING)
            {
                APP_ERROR_CHECK(err_code);
            }
            break;

        default:
            APP_ERROR_HANDLER(pin_no);
            break;
    }
}

And in slave 2 only change button state value and read this value in central side and ON particular LED with respective slave signal.

Please help me how i can logic to convert this 3 slave code into one program code and will work if flashed into 3 devices. Whenever use press switch ON slave 1 device only LED 1 will ON at central side. If slave 1 device turn OFF and then user press switch ON slave 3 then only LED 3 will ON at central side. Meaning whenever any slave turn ON/OFF switch press at that time respective LEDs only ON as defined in program not depend on connection handle.

Because connection handle changed due to slave power ON and OFF not in order. But in central code LED will fixed for respective signal coming from slaves.

Will please provide me program snippet how i can do this logic??

We are stuff here and also not much more time for this project.

If you need my both central and slaves complete projects files just let me know i can share with you but before that please do this case as private.

Thanks in advanced..!!!

RE: How LED ON at same time in Central connected to 3 ble peripheral.

Susheel Nuguru — Mon, 03 Sep 2018 07:40:50 GMT

Sorry for late reply.

You need to check if a notification is sent to the central. You can sniff the air packets to see if anything is sent on a button press.

RE: How LED ON at same time in Central connected to 3 ble peripheral.

Samarth — Mon, 27 Aug 2018 16:49:02 GMT

Hi Aryan,

I have added battery level characteristics in my both programs. In ble peripheral i have used BAS_ENABLED and in Central i have used BAS_C_ENABLED. When i push button at peripheral side i called battery_level_update() function.

But problem is not getting battery read event at central side. After that for checking purpose i have connect my phone with nRF Connect app to ble peripheral and checked battery services and it shows and also read battery level in android app. But not getting in central device will please help me where should exactly problem, how i can identify this.

I have added all required services in Central for read battery level.

Thanks...!!

RE: How LED ON at same time in Central connected to 3 ble peripheral.

Susheel Nuguru — Mon, 13 Aug 2018 12:16:41 GMT

The one in the example gives you a simulated battery level. You need to get the battery level as mentioned in the thread here. Even though the thread is for nRF51, the technique remains the same. There are lot of information in this forum for this. Please check the other threads on how to do this.

RE: How LED ON at same time in Central connected to 3 ble peripheral.

Samarth — Sun, 12 Aug 2018 06:46:34 GMT

Hi Aryan,

As per your suggestion now i am able to add battery service in my modified blinky example. i use ble_bas source and library file. But how i can read this battery level in my multilink example. How i can read battery service characteristics at multilink central side when press button.

For reference i refer ble_app_hrs_c example from sdk 15.0 but not able to read battery level. will you please provide me example for the same. so i can refer i modify my current multi-link central code with read battery level characterstics.

Thanks you so much.....

RE: How LED ON at same time in Central connected to 3 ble peripheral.

Susheel Nuguru — Thu, 09 Aug 2018 08:36:51 GMT

Hi Parag,

Unfortunately we do not have resources to make code snippets for all the possible designs on our chip. But this should not be hard.

if you check the SDK15\examples\ble_peripheral\ble_app_bps\main.c line 397 -> timers_init()

You can see that in timers_init function we used battery_level_meas_timeout_handler as a timeout callback function This means that a battery level update is sent to the peer everytime the timer expires.

In your case you need to call battery_level_meas_timeout_handler (maybe rename this to battery_level_meas_button_push_handler) in bsp_event_handler for example like this

static void bsp_event_handler(bsp_event_t event)
{
    ret_code_t err_code;

    switch (event)
    {
        case ...
        case ...
        case BSP_EVENT_KEY_0:
            battery_level_update();
            break;

        default:
            break;
    }
}

ofcourse you need to initialize bas service as you can see in services_init() function here.

The examples uses simulated sensor data to get the battery_level,but you can get this from the ADC sample on your input voltage pin as described here

RE: How LED ON at same time in Central connected to 3 ble peripheral.

Samarth — Thu, 09 Aug 2018 07:39:25 GMT

Thanks for your response...!!!

I have checked this ble_battery library but unable to understand how to add this with "Nordic_Blinky" example. Will you please provide me program example including battery service and blinky example.

I am able to add battery service with Blinky example but how i send this battery level when i press button to Multilink central board. will you please also provide small program snippet for the same.

Thanks..!!

RE: How LED ON at same time in Central connected to 3 ble peripheral.

Susheel Nuguru — Wed, 08 Aug 2018 10:42:12 GMT

Hi,

you need to configure the button using button library. And when the button is pressed, your registered callback will be called and in that callback you need to use ble_battery library to be able to transmit battery information.

RE: How LED ON at same time in Central connected to 3 ble peripheral.

Samarth — Tue, 07 Aug 2018 17:34:04 GMT

Thanks for your reply...

I have able to handle this with connection handle..

Now how i can send battery percentage level at the time of switch press. We want to send battery level as well because out devices is operated on battery.

Please suggest me best solution for that.

Thanks...

RE: How LED ON at same time in Central connected to 3 ble peripheral.

Susheel Nuguru — Wed, 01 Aug 2018 12:22:46 GMT

sorry for the late reply, we had some summer holidays here in Norway, hence the delays.

You should be able to use p_lbs_c_evt->conn_handle (in addition to the button_state you already are checking) to decide which connection it is and switch the appropriate LED on/off.

RE: How LED ON at same time in Central connected to 3 ble peripheral.

Samarth — Sun, 22 Jul 2018 11:39:34 GMT

Hi,

Thanks for your suggestion..

As per connection handle is working with one button and one LED but in my application in each connection handle having two switch and two LEDs.

I am able to add two switch in blinky example. like this:

static app_button_cfg_t buttons[] =
{
{LEDBUTTON_BUTTON1, false, BUTTON_PULL, button_event_handler},
{LEDBUTTON_BUTTON2, false, BUTTON_PULL, button_event_handler}
};

When i press button 1 and 2 is working fine in blinky.

But in multi-link central How i can identify which button state change to ON particular button LED in same connection handle 0.

I have checked in lbs_c_evt_handler(...)

 case BLE_LBS_C_EVT_BUTTON_NOTIFICATION:
        {
            NRF_LOG_INFO("Link 0x%x, Button state changed on peer to 0x%x",
                         p_lbs_c_evt->conn_handle,
                         p_lbs_c_evt->params.button.button_state);

            if (p_lbs_c_evt->params.button.button_state)
            {
                bsp_board_led_on(LEDBUTTON_LED);
            }
            else
            {
                bsp_board_led_off(LEDBUTTON_LED);
            }
        } break; // BLE_LBS_C_EVT_BUTTON_NOTIFICATION

When i press button 1 and 2 the event is coming for two button ON same LED because having same same connection link. I want ON particular LED with when particular button press.

How i can switch in central if second button press with same link. will please provide me small program snippet.

Thanks......

RE: How LED ON at same time in Central connected to 3 ble peripheral.

Susheel Nuguru — Tue, 03 Jul 2018 06:40:42 GMT

1) on the central side, in the ble_evt_handler

void ble_evt_handler(ble_evt_t const * p_ble_evt, void * p_context)

You have uint16_t conn_handle = p_ble_evt->evt.gap_evt.conn_handle;

This connection is unique per connection and you can use it to identify the peripheral logically.

2) Even though you press all the switches at the same time, the central will have to process them separately as each peripheral will send this notification to central separately.

For example,

if(the notification is for the LED service)
{
    if(conn_handle == 0x0 ) 
    {
        if(value == 1)    LED_X_ON;
        else LED_X_OFF;
    }
    
    else if(conn_handle == 0x1 ) 
    {
        if(value == 1)    LED_Y_ON;
        else LED_Y_OFF;
    }
    
    else if(conn_handle == 0x2 ) 
    {
        if(value == 1)    LED_Z_ON;
        else LED_Z_OFF;
    }
}

I am just giving you a pseudo code to give you an idea.

RE: How LED ON at same time in Central connected to 3 ble peripheral.

Samarth — Mon, 02 Jul 2018 17:59:27 GMT

Thanks for your response,

For my first ques, I am trying with connection handle but not getting. Will you please provide me small program snippet for how i can set address and ON LED with particular connection link.

And my second question i know wake up with GPIO sense signal it not problem, My other problem is as per above description device A B and C connected each device 2 switches press all same time then want to ON all LED on central with same time frame.

Thanks..

RE: How LED ON at same time in Central connected to 3 ble peripheral.

Susheel Nuguru — Mon, 02 Jul 2018 16:17:52 GMT

Hi Parag,

You answered your own question.

1) You can identify the peer device either by peer device device address or the connection handle. Adding an if else statement to turnon LEDs based on the connection ID from where the request came from is not that difficult. I am assuming that you are sending the switch state from peripherals to central using notifications. Then this logic should go into the notification handler for the service central discovered.

2) For the peripheral to wakeup on the button(switch) press, you need to configure the gpio to wake the peripheral on the state change. You can see how it is done here.