nRF21540EK integration with nRF5340dk

Hi there,

We are trying to integrate an nRF21540EK shield onto our nRF5340DK. Following the instructions on the following link (https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/ug_radio_fem.html#ug-radio-fem-nrf21540-ek-programming) we were able to set up the hardware but we are struggling to find a guide on how to configure the software.

We are seeking to use the nRF21540EK in conjunction with the "Bluetooth: Peripheral UART" sample found in the nRF connect SDK and would like to be able to control the gain and antenna select functions on the nRF21540.

Thanks,

Matt

Parents

0 Kazi Afroza Sultana over 3 years ago

Hello Mathew,

We have an example for peripheral_uart which was tested on NCS 1.8.0

The added configuration for nrf21540 are like the following configurations

# FEM
CONFIG_MPSL_FEM=y
CONFIG_BT_CTLR_TX_PWR_DYNAMIC_CONTROL=y
CONFIG_MPSL_FEM_NRF21540_RX_GAIN_DB=0
CONFIG_MPSL_FEM_NRF21540_TX_GAIN_DB=20

It also needs a function for setting transmit power and for the getting transmit power.

static void set_tx_power(uint8_t handle_type, uint16_t handle, int8_t tx_pwr_lvl)
{
    struct bt_hci_cp_vs_write_tx_power_level *cp;
    struct bt_hci_rp_vs_write_tx_power_level *rp;
    struct net_buf *buf, *rsp = NULL;
    int err;

    buf = bt_hci_cmd_create(BT_HCI_OP_VS_WRITE_TX_POWER_LEVEL,
                sizeof(*cp));
    if (!buf) {
        printk("Unable to allocate command buffer\n");
        return;
    }

    cp = net_buf_add(buf, sizeof(*cp));
    cp->handle = sys_cpu_to_le16(handle);
    cp->handle_type = handle_type;
    cp->tx_power_level = tx_pwr_lvl;

    err = bt_hci_cmd_send_sync(BT_HCI_OP_VS_WRITE_TX_POWER_LEVEL,
                   buf, &rsp);
    if (err) {
        uint8_t reason = rsp ?
            ((struct bt_hci_rp_vs_write_tx_power_level *)
              rsp->data)->status : 0;
        printk("Set Tx power err: %d reason 0x%02x\n", err, reason);
        return;
    }

    rp = (void *)rsp->data;
    printk("RADIO Tx Power: %d + PA_GAIN(%d) = %d\n", rp->selected_tx_power, CONFIG_MPSL_FEM_NRF21540_TX_GAIN_DB, rp->selected_tx_power + CONFIG_MPSL_FEM_NRF21540_TX_GAIN_DB);

    net_buf_unref(rsp);
}

static void get_tx_power(uint8_t handle_type, uint16_t handle, int8_t *tx_pwr_lvl)
{
    struct bt_hci_cp_vs_read_tx_power_level *cp;
    struct bt_hci_rp_vs_read_tx_power_level *rp;
    struct net_buf *buf, *rsp = NULL;
    int err;

    *tx_pwr_lvl = 0xFF;
    buf = bt_hci_cmd_create(BT_HCI_OP_VS_READ_TX_POWER_LEVEL,
                sizeof(*cp));
    if (!buf) {
        printk("Unable to allocate command buffer\n");
        return;
    }

    cp = net_buf_add(buf, sizeof(*cp));
    cp->handle = sys_cpu_to_le16(handle);
    cp->handle_type = handle_type;

    err = bt_hci_cmd_send_sync(BT_HCI_OP_VS_READ_TX_POWER_LEVEL,
                   buf, &rsp);
    if (err) {
        uint8_t reason = rsp ?
            ((struct bt_hci_rp_vs_read_tx_power_level *)
              rsp->data)->status : 0;
        printk("Read Tx power err: %d reason 0x%02x\n", err, reason);
        return;
    }

    rp = (void *)rsp->data;
    *tx_pwr_lvl = rp->tx_power_level;

    net_buf_unref(rsp);
}

static void connected(struct bt_conn *conn, uint8_t err)
{
	struct bt_conn *default_conn;
	uint16_t default_conn_handle;
	int ret;
	int8_t txp;

	char addr[BT_ADDR_LE_STR_LEN];

	if (err) {
		printk("Connection failed (err %u)\n", err);
		sys_reboot();
		return;
	}

	default_conn = bt_conn_ref(conn);
	ret = bt_hci_get_conn_handle(default_conn,
						&default_conn_handle);
	if (ret) {
		printk("No connection handle (err %d)\n", ret);
		sys_reboot();
		return;
	}
	
	bt_addr_le_to_str(bt_conn_get_dst(conn), addr, sizeof(addr));
			printk("Connected via connection (%d) at %s\n",
			       default_conn_handle, addr);
			get_tx_power(BT_HCI_VS_LL_HANDLE_TYPE_CONN,
				     default_conn_handle, &txp);
			printk("Connection (%d) - Initial Radio Tx Power: %d + PA_GAIN (%d) = %d\n",
			       default_conn_handle, txp, CONFIG_MPSL_FEM_NRF21540_TX_GAIN_DB, txp + CONFIG_MPSL_FEM_NRF21540_TX_GAIN_DB);

			set_tx_power(BT_HCI_VS_LL_HANDLE_TYPE_CONN,
				     default_conn_handle,
				     TRANSMIT_POWER_dBm);
			get_tx_power(BT_HCI_VS_LL_HANDLE_TYPE_CONN,
				     default_conn_handle, &txp);
			printk("Connection (%d) - Initial Radio Tx Power: %d + PA_GAIN (%d) = %d\n",
			       default_conn_handle, txp, CONFIG_MPSL_FEM_NRF21540_TX_GAIN_DB, txp + CONFIG_MPSL_FEM_NRF21540_TX_GAIN_DB);

	current_conn = bt_conn_ref(conn);

	dk_set_led_on(CON_STATUS_LED);
}

Set_tx_power has to be called from disconnected function to define the transmit power value.

static void disconnected(struct bt_conn *conn, uint8_t reason)
{
	char addr[BT_ADDR_LE_STR_LEN];
	int err = 0;

	bt_addr_le_to_str(bt_conn_get_dst(conn), addr, sizeof(addr));

	printk("Disconnected: %s (reason %u)\n", log_strdup(addr), reason);

	if (auth_conn) {
		bt_conn_unref(auth_conn);
		auth_conn = NULL;
	}

	if (current_conn) {
		bt_conn_unref(current_conn);
		current_conn = NULL;
		dk_set_led_off(CON_STATUS_LED);
	}

	err = bt_le_adv_start(BT_LE_ADV_CONN, ad, ARRAY_SIZE(ad), sd,
			      ARRAY_SIZE(sd));
	if (err) {
		printk("Advertising failed to start (err %d)\n", err);
		sys_reboot();
		return;
	}

	set_tx_power(BT_HCI_VS_LL_HANDLE_TYPE_ADV, 0, TRANSMIT_POWER_dBm);
}

From main function set_tx_power has to be called.

void main(void) {
....
..

set_tx_power(BT_HCI_VS_LL_HANDLE_TYPE_ADV, 0, TRANSMIT_POWER_dBm);

}

You can try this modification in peripheral_uart sample and see the output.

Let us know the consequence.

Thanks.

Best Regards,

Kazi Afroza Sultana

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