Sleep in connected mode

[Reshmi Marimganti]

Question:

From ble device I have to send some data or character to mobile in connected mode. After sending that data the device is not going to sleep mode while connected condition.

if I use sleep mode function, the device gets disconnected with the mobile. so how can I make the device go to sleep mode while in connected mode.

What function I have to use?

[ToTo]

Where do you put the sleep mode function?

It should not disconnect !! Are you sure that it return NRF_SUCCESS after you excute it ? Maybe you use the fuction that needs sofdevice activation but you didn't enable it before using that function?

[Reshmi Marimganti]

I have added the sleep code inside BLE_GAP_EVENT_CONNECTED

switch (p_ble_evt->header.evt_id)    
{    
    case BLE_GAP_EVT_CONNECTED:    
        err_code = bsp_indication_set(BSP_INDICATE_CONNECTED);    
        APP_ERROR_CHECK(err_code);    
        
        m_advertising_mode = BLE_NO_ADV;   
        m_conn_handle      = p_ble_evt->evt.gap_evt.conn_handle;    
			
	nrf_delay_ms(2000);   
		      
uint32_t err_code = bsp_indication_set(BSP_INDICATE_IDLE);
APP_ERROR_CHECK(err_code);

// Prepare wakeup buttons.    
err_code = bsp_btn_ble_sleep_mode_prepare();    
APP_ERROR_CHECK(err_code);      

// Go to system-off mode (this function will not return; wakeup will cause a reset).    
err_code = sd_power_system_off();    
APP_ERROR_CHECK(err_code);   
	       
 break;

[Stefan Birnir Sverrisson]

Hi Reshmi

There are mainly two low power modes

• System On, low power mode (CPU disabled, all nRF5x peripherals enabled)
• System Off mode, (CPU disabled, peripherals disabled)

Most or all examples in the SDK5 SDK 11.0.0 put the nRF5x device periodically into low power mode when connected with a peer device.

Recommended reading on how the low power modes work is given in the nRF51 Series reference manual and in the nRF52832 PS. There is also info in the nRF51 current consumption guide, chapter "Low power mode with BLE softdevice"