RE: Add a supplemetnary button and led on Blinky exemple

Saagar — Mon, 07 Sep 2020 09:03:47 GMT

Hi Jorn

After making above changes, If i press button_1 led_1 will glow and if i press button_2 then both leds led1 and led2 will glow

i am not getting why led1 is glowing after pressing button2. please help

board used :- nrf52_pca10040

sdk :- 11.0

RE: Add a supplemetnary button and led on Blinky exemple

run_ar — Mon, 19 Mar 2018 09:21:51 GMT

Handling in:129094

RE: Add a supplemetnary button and led on Blinky exemple

mc — Wed, 25 Oct 2017 16:32:18 GMT

Hello Jorn Froysa

Thank you very much!!! Now we can push the button on the peripheral and the correct leds toggel on the central!

To do it from central to the peripheral we have a problem: We not see the "case BLE_LBS_C_EVT_BUTTON_NOTIFICATION" in the peripheral. We see only the "led write handler" What we have to change there?

/**@brief Function for handling write events to the LED characteristic.

@param[in] p_lbs Instance of LED Button Service to which the write applies.
@param[in] led_state Written/desired state of the LED. */ static void led_write_handler(ble_lbs_t * p_lbs, uint8_t led_state) { if (led_state)

{
```
 bsp_board_led_on(LEDBUTTON_LED_PIN);
 	  NRF_LOG_INFO("Received LED ON!\r\n");
 	
```
} else { bsp_board_led_off(LEDBUTTON_LED_PIN); NRF_LOG_INFO("Received LED OFF!\r\n"); }

}

Can you plase send us the modification? We would very apppreciate! Best regards MC

RE: Add a supplemetnary button and led on Blinky exemple

Jørn — Wed, 25 Oct 2017 12:42:52 GMT

Hello mc

There are a few ways you can achieve this. You could create a new characteristic for the second button, or you could use the one already there. I threw together a quick solution using the characteristic already present. Do note this solution may not be the optimal way of doing it, it's just for guidance.

The way the blinky example works at the peripheral is that GPIOTE generates an interrupt, this identifies it as a port event, then calls the button handler in the app_buttons module, which creates a variable called transition, which is passed on to the button_event_handler in main.c. The transition variable is set to 1 if the button transition led to the pins "active state", and zero otherwise. The active state is defined when calling app_buttons_init, in the buttons_init function in main. In the example the active state attribute is set to "false" which corresponds to 0.

The button_event_handler then calls the ble_lbs_on_button_change function which sends the transition value to the client.

The changes I made here defines a new button, LEDBUTTON_BUTTON_PIN2, and registers this with the app_button module in buttons_init. The button config now looks like this

static app_button_cfg_t buttons[] =
{
    {LEDBUTTON_BUTTON_PIN, false, BUTTON_PULL, button_event_handler},
    {LEDBUTTON_BUTTON_PIN2, false, BUTTON_PULL, button_event_handler}
};

I then altered the switch in button_event_handler

switch (pin_no)
{
    case LEDBUTTON_BUTTON_PIN:
        NRF_LOG_INFO("Send button1 state change.\r\n");            
        err_code = button_action ? ble_lbs_on_button_change(&m_lbs, 1) : ble_lbs_on_button_change(&m_lbs, 0);
        if (err_code != NRF_SUCCESS &&
            err_code != BLE_ERROR_INVALID_CONN_HANDLE &&
            err_code != NRF_ERROR_INVALID_STATE)
        {
            APP_ERROR_CHECK(err_code);
        }
        break;
					
	case LEDBUTTON_BUTTON_PIN2:
		NRF_LOG_INFO("Send button2 state change.\r\n");            
		err_code = button_action ? ble_lbs_on_button_change(&m_lbs, 3) : ble_lbs_on_button_change(&m_lbs, 2);
        if (err_code != NRF_SUCCESS &&
            err_code != BLE_ERROR_INVALID_CONN_HANDLE &&
            err_code != NRF_ERROR_INVALID_STATE)
        {
            APP_ERROR_CHECK(err_code);
        }
				break;

    default:
        APP_ERROR_HANDLER(pin_no);
        break;
}

This sends a 0 or 1 if the first button is released/pressed, and a 2 or 3 if the second button is released/pressed.

On the client side you define a second LED, and then alter the following case in lbs_c_evt_handler in main

case BLE_LBS_C_EVT_BUTTON_NOTIFICATION:
        {
            NRF_LOG_INFO("Button state changed on peer to 0x%x.\r\n", p_lbs_c_evt->params.button.button_state);
            if (p_lbs_c_evt->params.button.button_state==0x1)
            {
                bsp_board_led_on(LEDBUTTON_LED);
            }
            else if(p_lbs_c_evt->params.button.button_state==0x0)
            {
                bsp_board_led_off(LEDBUTTON_LED);
            }
            else if(p_lbs_c_evt->params.button.button_state==0x3)
            {
                bsp_board_led_on(LEDBUTTON_LED2);
            }
            else
            {
                bsp_board_led_off(LEDBUTTON_LED2);
            }						
        } break; // BLE_LBS_C_EVT_BUTTON_NOTIFICATION

This toggles the correct led depending on what value was received from the server.

You will need to add similar changes (but reverse roles) for an extra button at the central.

Best regards

Jørn Frøysa