How to get rssi without connection via central device

RE: How to get rssi without connection via central device

endnode — Fri, 21 Jul 2017 12:02:07 GMT

It doesn't make much sense, the whole application is asynchronous:

Get some interrupt or event => call some function (which might disable/enable more events).
Wait for next event (whatever it is).

So just during boot set all initial events you are waiting for and then do in event handlers (button press or SD callbacks) what you want to do.

RE: How to get rssi without connection via central device

purgoufr — Fri, 21 Jul 2017 11:57:09 GMT

I want to build a conditional structure. The first button press will process BLE_GAP_EVT_ADV_REPORT and BLE_GAP_EVT_CONNECTED.(so connection establish occur). The second button press will only process the BLE_GAP_EVT_ADV_REPORT and get the rss data( Not connected, just get rssi value).

RE: How to get rssi without connection via central device

endnode — Fri, 21 Jul 2017 08:39:38 GMT

Well you must then have something wrong in the code because if you scan only no connection is established, you will be just getting BLE_GAP_EVT_ADV_REPORT events. You can parse event data to get RSSI value out of it. Once you like it just simply call connect function which you normally call in button press handler. Don't see a problem, sorry.

RE: How to get rssi without connection via central device

purgoufr — Fri, 21 Jul 2017 08:06:37 GMT

I want to continuously get rssi value of the peripheral device using the central device without connection. Normally I start the scan_start function using button_handler function. Then connection establish occurs. But I dont want to do that. I want to Connect automatically device without press the button (without button_handler function). And I want the device not to reconnect until it leaves the bluetooth signal range.(think like KEYLESS GO - Mercedes). Is it possible?

RE: How to get rssi without connection via central device

purgoufr — Fri, 21 Jul 2017 06:39:01 GMT

But I want to do this;

scan_start();
Get Rssi value
If Rssi value > some_value
Connect automatically device without press the button (without button_handler function)

RE: How to get rssi without connection via central device

endnode — Fri, 21 Jul 2017 06:37:57 GMT

Yes, looks good.

RE: How to get rssi without connection via central device

purgoufr — Fri, 21 Jul 2017 06:36:22 GMT

Normally process going like this;

static void button_handler(uint8_t pin_no, uint8_t button_action)
{
    if(button_action == APP_BUTTON_PUSH || button_action == BSP_BUTTON_ACTION_LONG_PUSH || BSP_BUTTON_ACTION_RELEASE)
    {
        switch(pin_no)
        {
            case BUTTON_1:
                scan_start();
                break;
          
	default:
		break;
						
	}
   }
}

THEN

static void on_ble_evt(ble_evt_t * p_ble_evt)
{
    uint32_t              err_code;
    const ble_gap_evt_t * p_gap_evt = &p_ble_evt->evt.gap_evt;	 
	
    switch (p_ble_evt->header.evt_id)
    {
        case BLE_GAP_EVT_ADV_REPORT:
         .
         .
 
         case BLE_GAP_EVT_CONNECTED:
         .
         .

RE: How to get rssi without connection via central device

endnode — Fri, 21 Jul 2017 06:34:22 GMT

Yes, this will start the scanning, now you just need to handle incoming events. Good luck!

RE: How to get rssi without connection via central device

purgoufr — Fri, 21 Jul 2017 05:59:47 GMT

I try to read rssi like adc_value. I want to keep watching. I have two buttons. I just want to use first button manually. So try to connect every time I press it. When I press the second button(I only pressed the second button once), Central device always search peripheral device and it always try to connect automatically if the rssi value is at a certain level. (Connect to the peripheral device without pressing the button.)

scan_start function ;

static void scan_start(void)
{
    uint32_t err_code;
	
    err_code = sd_ble_gap_scan_start(&m_scan_params);
    APP_ERROR_CHECK(err_code);
    
    err_code = bsp_indication_set(BSP_INDICATE_SCANNING);
    APP_ERROR_CHECK(err_code);
	
}

RE: How to get rssi without connection via central device

endnode — Thu, 20 Jul 2017 17:50:21 GMT

You probably deal with some specific FW code or example which I won't help you with but the procedure you are describing is scanning. See following chapter in Infocenter, there is sd_ble_gap_scan_start() function which should cause BLE_GAP_EVT_ADV_REPORT events coming and as you can see in event data you can locate RSSI measured.

RE: How to get rssi without connection via central device

purgoufr — Thu, 20 Jul 2017 17:39:48 GMT

It automatically connects to the peripheral device when it enters the on_ble_evt function. But I do not want that. I want to read rssi value without entering the peripheral device.Normally, when I press the button, it enters "button_handler" function. Then it use "sd_ble_gap_scan_start(&m_scan_params);" function. After that ,Function for handling the Application's BLE Stack events start automatically(on_ble_evt). Finally connection establihes. But I just want to learn rssi value of peripheral device,nothing else. Can you write some method or function to do that?

RE: How to get rssi without connection via central device

endnode — Thu, 20 Jul 2017 13:50:15 GMT

Sure, each scanning event (when you receive ADV_xxx packet) has RSSI value in the event data structure.