PA + LNA with BLE and Zigbee at the same time

[sjf]

Hi,

We have been working with a coordinator and a router device based on nRF52840 with nRF5_SDK_for_Thread_and_Zigbee_v4.0.0_dc7186b

Both devices are Zigbee 3.0 and implement Install Codes.

On the Coordinator we have Zigbee and BLE turned on at the same time on a Fanstel BT840X with integrated PA/LNA

We tried several things:

1.When running this code, BLE seems to work but Zigbee does not seem to send Link Status messages among others

ret_code_t pa_lna_init(uint32_t gpio_pa_pin, uint32_t gpio_lna_pin)
{
    ble_opt_t opt;
    uint32_t gpiote_ch = NULL;
    ret_code_t err_code;        

    nrf_gpio_cfg_output(APP_CPS_PIN);
    nrf_gpio_cfg_output(APP_CHL_PIN);
    nrf_gpio_pin_set(APP_CHL_PIN);	
    nrf_gpio_pin_clear(APP_CPS_PIN); //enable
    //nrf_gpio_pin_set(APP_CPS_PIN); //bypass
    nrf_gpio_cfg_output(APP_PA_PIN);
    nrf_gpio_pin_clear(APP_PA_PIN); //
    nrf_gpio_cfg_output(APP_LNA_PIN);
    nrf_gpio_pin_clear(APP_LNA_PIN); //

    memset(&opt, 0, sizeof(ble_opt_t));
    
    if (!nrf_drv_gpiote_is_init())
    {
      err_code = nrf_drv_gpiote_init();
      if(err_code != NRF_ERROR_INVALID_STATE)
          APP_ERROR_CHECK(err_code);
    }
    
    err_code = nrf_drv_ppi_init();
    if(err_code != NRF_ERROR_MODULE_ALREADY_INITIALIZED)
        APP_ERROR_CHECK(err_code);
    
    nrf_ppi_channel_t ppi_set_ch;
    nrf_ppi_channel_t ppi_clr_ch;
    
    err_code = nrf_drv_ppi_channel_alloc(&ppi_set_ch);
    APP_ERROR_CHECK(err_code);
    
    err_code = nrf_drv_ppi_channel_alloc(&ppi_clr_ch);
    APP_ERROR_CHECK(err_code);

    nrf_drv_gpiote_out_config_t config = GPIOTE_CONFIG_OUT_TASK_TOGGLE(false);
    
    if((gpio_pa_pin == NULL) && (gpio_lna_pin == NULL))
    {
        err_code = NRF_ERROR_INVALID_PARAM;
        APP_ERROR_CHECK(err_code);
    }    

    if(gpio_pa_pin != NULL)
    {
        if(gpiote_ch == NULL)
        {
            // nrf_drv_gpiote_out_uninit(gpio_pa_pin);
            err_code = nrf_drv_gpiote_out_init(gpio_pa_pin, &config);
            APP_ERROR_CHECK(err_code);
            
            gpiote_ch = nrf_drv_gpiote_out_task_addr_get(gpio_pa_pin); 
        }
        
        // PA config
        opt.common_opt.pa_lna.pa_cfg.active_high = 1;   // Set the pin to be active high
        opt.common_opt.pa_lna.pa_cfg.enable      = 1;   // Enable toggling
        opt.common_opt.pa_lna.pa_cfg.gpio_pin    = gpio_pa_pin; // The GPIO pin to toggle tx  
    }
    
    if(gpio_lna_pin != NULL)
    {
        if(gpiote_ch == NULL)
        {
            // nrf_drv_gpiote_out_uninit(gpio_lna_pin);
            err_code = nrf_drv_gpiote_out_init(gpio_lna_pin, &config);
            APP_ERROR_CHECK(err_code);        
            
            gpiote_ch = nrf_drv_gpiote_out_task_addr_get(gpio_lna_pin); 
        }
        
        // LNA config
        opt.common_opt.pa_lna.lna_cfg.active_high  = 1; // Set the pin to be active high
        opt.common_opt.pa_lna.lna_cfg.enable       = 1; // Enable toggling
        opt.common_opt.pa_lna.lna_cfg.gpio_pin     = gpio_lna_pin;  // The GPIO pin to toggle rx
    }

    // Common PA/LNA config
    opt.common_opt.pa_lna.gpiote_ch_id  = (gpiote_ch - NRF_GPIOTE_BASE) >> 2;   // GPIOTE channel used for radio pin toggling
    opt.common_opt.pa_lna.ppi_ch_id_clr = ppi_clr_ch;   // PPI channel used for radio pin clearing
    opt.common_opt.pa_lna.ppi_ch_id_set = ppi_set_ch;   // PPI channel used for radio pin setting
    
    err_code = sd_ble_opt_set(BLE_COMMON_OPT_PA_LNA, &opt);
    // APP_ERROR_CHECK(err_code);    

    return err_code;
}

2. When setting at sdk_config.h FEM_CONTROL_DEFAULT_ENABLE to 1 (and other FEM_CONTROL_DEFAULT_XXX for pins), BLE stops working...

So, we would like to know which is the right approach to get Zigbee and BLE working at the same time with PA/LNA

Regards,

Santiago

[Edvin]

And the radio driver repository is found here:

github.com/.../nRF-IEEE-802.15.4-radio-driver

[sjf]

Thanks so much. We will try to update this.

[sjf]

Hi, we tried these and by modifying pa and lna time gap settings it started to send some messges. Anyway, Wireshark logs show that with the times selected there are multiple retransmissions from devices to coordinator (which has the PA/LNA module)

is there any recommendation on these settings? 

Thanks in advance

[Edvin]

What do you mean by this? Are there one retransmission? Many? On every packet? Or only occasionally?

[sjf]

Hi Edvin,

By setting NRF_FEM_PA_TIME_IN_ADVANCE_US and NRF_FEM_LNA_TIME_IN_ADVANCE_US to their default values (23 and 5 us) there is nothing logged into Wireshark.

When tried some other values (i.e. 40us for both values) we can see that data is sent from the device and sometimes received, but there are several retransmissions from other devices when sending reports to this device (on every packet, not occasionally).

Regards