Hi,
I am working on the client program to retrieve the value from 4 characteristics at the same time using notifications. I have already done with the server program. Using nrf connect to connect with my program, it looks like this:
I would like to collect the value from these four characteristics using notifications. Here' s the code to update 4 characteristic data on server:
void ble_eeg_update_4ch(ble_eeg_t *p_eeg) {
//packet 1:
uint32_t err_code;
if (p_eeg->conn_handle != BLE_CONN_HANDLE_INVALID && p_eeg->ads1299_current_configuration[4] != 0xE1) {
uint16_t hvx_len = EEG_PACKET_LENGTH;//The length is 60
ble_gatts_hvx_params_t const hvx_params = {
.handle = p_eeg->eeg_ch1_handles.value_handle,
.type = BLE_GATT_HVX_NOTIFICATION,
.offset = 0,
.p_len = &hvx_len,
.p_data = p_eeg->eeg_ch1_buffer,
};
err_code = sd_ble_gatts_hvx(p_eeg->conn_handle, &hvx_params);
}
if (err_code == NRF_ERROR_RESOURCES) {
NRF_LOG_INFO("sd_ble_gatts_hvx() ERR/RES: 0x%x\r\n", err_code);
}
//Packet 2
if (p_eeg->conn_handle != BLE_CONN_HANDLE_INVALID && p_eeg->ads1299_current_configuration[5] != 0xE1) {
uint16_t hvx_len = EEG_PACKET_LENGTH;//The length is 60
ble_gatts_hvx_params_t const hvx_params = {
.handle = p_eeg->eeg_ch2_handles.value_handle,
.type = BLE_GATT_HVX_NOTIFICATION,
.offset = 0,
.p_len = &hvx_len,
.p_data = p_eeg->eeg_ch2_buffer,
};
err_code = sd_ble_gatts_hvx(p_eeg->conn_handle, &hvx_params);
}
if (err_code == NRF_ERROR_RESOURCES) {
NRF_LOG_INFO("sd_ble_gatts_hvx() ERR/RES: 0x%x\r\n", err_code);
}
//Packet 3
if (p_eeg->conn_handle != BLE_CONN_HANDLE_INVALID && p_eeg->ads1299_current_configuration[6] != 0xE1) {
uint16_t hvx_len = EEG_PACKET_LENGTH;//The length is 60
ble_gatts_hvx_params_t const hvx_params = {
.handle = p_eeg->eeg_ch3_handles.value_handle,
.type = BLE_GATT_HVX_NOTIFICATION,
.offset = 0,
.p_len = &hvx_len,
.p_data = p_eeg->eeg_ch3_buffer,
};
err_code = sd_ble_gatts_hvx(p_eeg->conn_handle, &hvx_params);
}
if (err_code == NRF_ERROR_RESOURCES) {
NRF_LOG_INFO("sd_ble_gatts_hvx() ERR/RES: 0x%x\r\n", err_code);
}
//Packet 4
if (p_eeg->conn_handle != BLE_CONN_HANDLE_INVALID && p_eeg->ads1299_current_configuration[7] != 0xE1) {
uint16_t hvx_len = EEG_PACKET_LENGTH;//The length is 60
ble_gatts_hvx_params_t const hvx_params = {
.handle = p_eeg->eeg_ch4_handles.value_handle,
.type = BLE_GATT_HVX_NOTIFICATION,
.offset = 0,
.p_len = &hvx_len,
.p_data = p_eeg->eeg_ch4_buffer,
};
err_code = sd_ble_gatts_hvx(p_eeg->conn_handle, &hvx_params);
}
if (err_code == NRF_ERROR_RESOURCES) {
NRF_LOG_INFO("sd_ble_gatts_hvx() ERR/RES: 0x%x\r\n", err_code);
}
}
Question:
1. Do you have examples that have multiple characteristics that need notifications in one service? I read the code of ble_app_hrs_c, but this program is not what I want.
2. If I can get retrieve these 4 characteristics data on the client, how to differentiate them?
