nRF 蓝牙一从对应多主
一从对多主例程路径：examples\ble_peripheral\experimental\ble_app_multiperipheral\pca10040\s132\arm5_no_packs
SDK15.3：
与普通流程不同:
一从对多主在连接时可同时存在n个连接句柄（conn_handle），具体多少个，需要看NRF_SDH_BLE_PERIPHERAL_LINK_COUNT 与 NRF_SDH_BLE_TOTAL_LINK_COUNT的数值，在通讯过程中使用到QWR 队列写模块实现与多个主之间的通讯
在连接时会自带一个连接句柄，连接句柄具体值不固定在0到n-1之间变化，断开后则变成0xFF
nus服务通讯过程中:
ble_nus_evt_t --> conn_handle也带有连接句柄参数，可与建立连接时的连接句柄对应上，也可用这个连接句柄做到，回复对应哪个主的操作
需要注意的几点：
ble_stack_init --> ble_evt_handler --> BLE_GAP_EVT_CONNECTED and BLE_GAP_EVT_DISCONNECTED
gatt_init --> 一对一：
err_code = nrf_ble_gatt_init(&m_gatt, gatt_evt_handler);
APP_ERROR_CHECK(err_code);
err_code = nrf_ble_gatt_att_mtu_periph_set(&m_gatt, NRF_SDH_BLE_GATT_MAX_MTU_SIZE);
APP_ERROR_CHECK(err_code);
一从对多主：
ret_code_t err_code = nrf_ble_gatt_init(&m_gatt, NULL);
APP_ERROR_CHECK(err_code);
services_init --> 一对一:
// Initialize Queued Write Module.
qwr_init.error_handler = nrf_qwr_error_handler;
err_code = nrf_ble_qwr_init(&m_qwr, &qwr_init);
APP_ERROR_CHECK(err_code);
// Initialize NUS.
memset(&nus_init, 0, sizeof(nus_init));
nus_init.data_handler = nus_data_handler;
err_code = ble_nus_init(&m_nus, &nus_init);
APP_ERROR_CHECK(err_code);
一从对多主:
ret_code_t err_code;
nrf_ble_qwr_init_t qwr_init = {0};
// Initialize Queued Write Module instances.
qwr_init.error_handler = nrf_qwr_error_handler;
for (uint32_t i = 0; i < LINK_TOTAL; i++)
{
err_code = nrf_ble_qwr_init(&m_qwr[i], &qwr_init);
APP_ERROR_CHECK(err_code);
}
uint32_t err_code;
ble_nus_init_t nus_init;
// Initialize NUS.
memset(&nus_init, 0, sizeof(nus_init));
nus_init.data_handler = nus_data_handler;
err_code = ble_nus_init(&m_nus, &nus_init);
APP_ERROR_CHECK(err_code);
ble_conn_state_init();
conn_params_init --> 一对一:
uint32_t err_code;
ble_conn_params_init_t cp_init;
memset(&cp_init, 0, sizeof(cp_init));
cp_init.p_conn_params = NULL;
cp_init.first_conn_params_update_delay = FIRST_CONN_PARAMS_UPDATE_DELAY;
cp_init.next_conn_params_update_delay = NEXT_CONN_PARAMS_UPDATE_DELAY;
cp_init.max_conn_params_update_count = MAX_CONN_PARAMS_UPDATE_COUNT;
cp_init.start_on_notify_cccd_handle = BLE_GATT_HANDLE_INVALID;
cp_init.disconnect_on_fail = false;
cp_init.evt_handler = on_conn_params_evt;
cp_init.error_handler = conn_params_error_handler;
err_code = ble_conn_params_init(&cp_init);
APP_ERROR_CHECK(err_code);
一从对多主:
ret_code_t err_code;
ble_conn_params_init_t cp_init;
memset(&cp_init, 0, sizeof(cp_init));
cp_init.p_conn_params = NULL;
cp_init.first_conn_params_update_delay = FIRST_CONN_PARAMS_UPDATE_DELAY;
cp_init.next_conn_params_update_delay = NEXT_CONN_PARAMS_UPDATE_DELAY;
cp_init.max_conn_params_update_count = MAX_CONN_PARAMS_UPDATE_COUNT;
cp_init.start_on_notify_cccd_handle = BLE_GATT_HANDLE_INVALID;
cp_init.disconnect_on_fail = true;
cp_init.error_handler = conn_params_error_handler;
err_code = ble_conn_params_init(&cp_init);
APP_ERROR_CHECK(err_code);具体操作流程，参考 16-享钥-wiegand-可多主连接 项目