This is an example based on mbed-os cellular APIs that demonstrates a TCP or UDP echo transaction with a public echo server. Included TPB23 NB-IoT module which is can use LGU+ in Korea.
This example is showing how to use the NB-IoT(SECOM TPB23 module) of LGU plus network in Korea. The NB-IoT module' seller provided a document on how to start based on Mbed OS 5.11. (Created by CodeZoo) This guide has been supported to the latest os version which included 5.12 ~ 5.15.
- if you need specific version of Mbed OS, please revision of TPB23_Driver and check it out.
- Pelion ready example code is here!
Requirement
- Need to check CodeZoo's s hardware a guide.
- Need a CodeZoo's NBIoT board and development board.
- Board picture & Jumper configure
- And also can use with mbed application shield, as shown below.

Tested with
- DISCO_L475VG_IOT01A - If you are in Korea, can buy here !
- NUCLEO_F429ZI - If you are in Korea, can buy here !
1. Import the application into your desktop
mbed import http://os.mbed.com/users/Daniel_Lee/code/mbed-os-example-cellular-TPB23/ cd mbed-os-example-cellular-TPB23
2. Compile and program
mbed compile -t <toolchain> -m <TARGET_BOARD>
(supported toolchains : GCC_ARM / ARM / IAR)
3. Download binary to a target board
4. Result
mbed-os-example-cellular Built: Aug 7 2019, 06:10:47 [MAIN], plmn: NULL Establishing connection [00000001ms][INFO][CELL]: New CellularContext (20000a08) [00000002ms][INFO][CELL]: CellularContext plmn NULL [00000003ms][INFO][CELL]: CellularContext connect [00000036ms][INFO][CELL]: RSSI -69 dBm [00000036ms][INFO][CELL]: Start connecting (timeout 1 s) [00000087ms][INFO][CELL]: RSSI -69 dBm [00000116ms][INFO][CELL]: Modem ready [00000146ms][INFO][CELL]: RSSI -69 dBm [00000146ms][INFO][CELL]: Setup SIM (timeout 1 s) [00001233ms][INFO][CELL]: Looked up APN internet [00001362ms][ERR ][CELL]: AT error code 50 [00001362ms][WARN][CELL]: Packet domain event reporting set failed! [00001393ms][INFO][CELL]: RSSI -65 dBm [00001393ms][INFO][CELL]: Network registration (timeout 180 s) [00001443ms][INFO][CELL]: Registering network => Attaching network [00001473ms][INFO][CELL]: RSSI -65 dBm [00001473ms][INFO][CELL]: Attaching network (timeout 60 s) [00001601ms][INFO][CELL]: Found PDP context 1 [00001649ms][INFO][CELL]: Activate PDP context 1 Connection Established. [00001671ms][INFO][CELL]: Socket 0 open [00001707ms][INFO][CELL]: Socket 1 open [00001748ms][INFO][CELL]: Socket create id: 1 [00001883ms][INFO][CELL]: Socket 1 sent 43 bytes to 8.8.8.8 port 53 [00004311ms][INFO][CELL]: Socket 1 recv 59 bytes from 8.8.8.8 port 53 [00004331ms][INFO][CELL]: Close socket: 1 error: 0 [00004331ms][INFO][CELL]: Socket 1 closed [00004373ms][INFO][CELL]: Socket create id: 1 TCP: connected with echo.mbedcloudtesting.com server [00004448ms][INFO][CELL]: Socket 0 sent 4 bytes to 52.215.34.155 port 7 TCP: Sent 4 Bytes to echo.mbedcloudtesting.com [00007560ms][INFO][CELL]: Socket 0 recv 4 bytes [00007580ms][INFO][CELL]: Close socket: 1 error: 0 [00007580ms][INFO][CELL]: Socket 0 closed Received from echo server 4 Bytes [00007581ms][INFO][CELL]: CellularContext disconnect() [00007630ms][INFO][CELL]: cb: CellularContext disconnected Success. Exiting
SERCOMM/TPB23/SERCOMM_TPB23_CellularStack.cpp
- Committer:
- Daniel_Lee
- Date:
- 2019-08-07
- Revision:
- 45:63eba30af193
File content as of revision 45:63eba30af193:
/*
* Copyright (c) 2017, Arm Limited and affiliates.
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "SERCOMM_TPB23_CellularStack.h"
#include "CellularUtil.h"
#include "CellularLog.h"
#define PACKET_SIZE_MAX 1500 //TPB23 Range is 12-1500
using namespace mbed;
using namespace mbed_cellular_util;
SERCOMM_TPB23_CellularStack::SERCOMM_TPB23_CellularStack(ATHandler &atHandler, int cid, nsapi_ip_stack_t stack_type) : AT_CellularStack(atHandler, cid, stack_type)
{
_at.set_urc_handler("+NSONMI:", mbed::Callback<void()>(this, &SERCOMM_TPB23_CellularStack::urc_nsonmi));
}
SERCOMM_TPB23_CellularStack::~SERCOMM_TPB23_CellularStack()
{
}
nsapi_error_t SERCOMM_TPB23_CellularStack::socket_listen(nsapi_socket_t handle, int backlog)
{
return NSAPI_ERROR_UNSUPPORTED;
}
nsapi_error_t SERCOMM_TPB23_CellularStack::socket_accept(void *server, void **socket, SocketAddress *addr)
{
return NSAPI_ERROR_UNSUPPORTED;
}
nsapi_error_t SERCOMM_TPB23_CellularStack::socket_connect(nsapi_socket_t handle, const SocketAddress &address)
{
CellularSocket *socket = (CellularSocket *)handle;
_at.lock();
if (!socket->created) {
const nsapi_error_t error_create = create_socket_impl(socket);
if (error_create != NSAPI_ERROR_OK) {
return error_create;
}
}
_at.cmd_start("AT+NSOCO=");
_at.write_int(socket->id);
_at.write_string(address.get_ip_address(), false);
_at.write_int(address.get_port());
_at.cmd_stop();
_at.resp_start();
_at.resp_stop();
_at.unlock();
if (_at.get_last_error() == NSAPI_ERROR_OK) {
socket->remoteAddress = address;
socket->connected = true;
return NSAPI_ERROR_OK;
}
return NSAPI_ERROR_NO_CONNECTION;
}
void SERCOMM_TPB23_CellularStack::urc_nsonmi()
{
int sock_id = _at.read_int();
for (int i = 0; i < get_max_socket_count(); i++) {
CellularSocket *sock = _socket[i];
if (sock && sock->id == sock_id) {
if (sock->_cb) {
sock->_cb(sock->_data);
}
break;
}
}
}
int SERCOMM_TPB23_CellularStack::get_max_socket_count()
{
return TPB23_SOCKET_MAX;
}
bool SERCOMM_TPB23_CellularStack::is_protocol_supported(nsapi_protocol_t protocol)
{
return (protocol == NSAPI_UDP || protocol == NSAPI_TCP);
}
nsapi_error_t SERCOMM_TPB23_CellularStack::socket_close_impl(int sock_id)
{
_at.cmd_start("AT+NSOCL=");
_at.write_int(sock_id);
_at.cmd_stop_read_resp();
tr_info("Close socket: %d error: %d", sock_id, _at.get_last_error());
return _at.get_last_error();
}
nsapi_error_t SERCOMM_TPB23_CellularStack::create_socket_impl(CellularSocket *socket)
{
int sock_id = -1;
bool socketOpenWorking = false;
if (socket->proto == NSAPI_UDP) {
_at.cmd_start("AT+NSOCR=DGRAM,17,");
} else if (socket->proto == NSAPI_TCP) {
_at.cmd_start("AT+NSOCR=STREAM,6,");
} else {
return NSAPI_ERROR_PARAMETER;
}
_at.write_int(socket->localAddress.get_port());
_at.write_int(1);
_at.cmd_stop();
_at.resp_start();
sock_id = _at.read_int();
_at.resp_stop();
socketOpenWorking = (_at.get_last_error() == NSAPI_ERROR_OK);
if (!socketOpenWorking) {
_at.cmd_start("AT+NSOCL=0");
_at.cmd_stop_read_resp();
if (socket->proto == NSAPI_UDP) {
_at.cmd_start("AT+NSOCR=DGRAM,17,");
} else if (socket->proto == NSAPI_TCP) {
_at.cmd_start("AT+NSOCR=STREAM,6,");
}
_at.write_int(socket->localAddress.get_port());
_at.write_int(1);
_at.cmd_stop();
_at.resp_start();
sock_id = _at.read_int();
_at.resp_stop();
socketOpenWorking = (_at.get_last_error() == NSAPI_ERROR_OK);
}
if (!socketOpenWorking || (sock_id == -1)) {
tr_error("Socket create failed!");
return NSAPI_ERROR_NO_SOCKET;
}
// Check for duplicate socket id delivered by modem
for (int i = 0; i < TPB23_SOCKET_MAX; i++) {
CellularSocket *sock = _socket[i];
if (sock && sock->created && sock->id == sock_id) {
tr_error("Duplicate socket index: %d created:%d, sock_id: %d", i, sock->created, sock_id);
return NSAPI_ERROR_NO_SOCKET;
}
}
tr_info("Socket create id: %d", sock_id);
socket->id = sock_id;
socket->created = true;
return NSAPI_ERROR_OK;
}
nsapi_size_or_error_t SERCOMM_TPB23_CellularStack::socket_sendto_impl(CellularSocket *socket, const SocketAddress &address,
const void *data, nsapi_size_t size)
{
int sent_len = 0;
if (size > PACKET_SIZE_MAX) {
return NSAPI_ERROR_PARAMETER;
}
char *hexstr = new char[size * 2 + 1];
int hexlen = char_str_to_hex_str((const char *)data, size, hexstr);
// NULL terminated for write_string
hexstr[hexlen] = 0;
if (socket->proto == NSAPI_UDP) {
_at.cmd_start("AT+NSOST=");
_at.write_int(socket->id);
_at.write_string(address.get_ip_address(), false);
_at.write_int(address.get_port());
_at.write_int(size);
} else if (socket->proto == NSAPI_TCP) {
_at.cmd_start("AT+NSOSD=");
_at.write_int(socket->id);
_at.write_int(size);
} else {
delete [] hexstr;
return NSAPI_ERROR_PARAMETER;
}
_at.write_string(hexstr, false);
_at.cmd_stop();
_at.resp_start();
// skip socket id
_at.skip_param();
sent_len = _at.read_int();
_at.resp_stop();
delete [] hexstr;
if (_at.get_last_error() == NSAPI_ERROR_OK) {
return sent_len;
}
return _at.get_last_error();
}
nsapi_size_or_error_t SERCOMM_TPB23_CellularStack::socket_recvfrom_impl(CellularSocket *socket, SocketAddress *address,
void *buffer, nsapi_size_t size)
{
nsapi_size_or_error_t recv_len = 0;
int port;
char ip_address[NSAPI_IP_SIZE];
_at.cmd_start("AT+NSORF=");
_at.write_int(socket->id);
_at.write_int(size <= PACKET_SIZE_MAX ? size : PACKET_SIZE_MAX);
_at.cmd_stop();
_at.resp_start();
// receiving socket id
_at.skip_param();
_at.read_string(ip_address, sizeof(ip_address));
port = _at.read_int();
recv_len = _at.read_int();
int hexlen = _at.read_hex_string((char *)buffer, size);
// remaining length
_at.skip_param();
_at.resp_stop();
if (!recv_len || (recv_len == -1) || (_at.get_last_error() != NSAPI_ERROR_OK)) {
return NSAPI_ERROR_WOULD_BLOCK;
}
if (address) {
address->set_ip_address(ip_address);
address->set_port(port);
}
if (recv_len != hexlen) {
tr_error("Not received as much data as expected. Should receive: %d bytes, received: %d bytes", recv_len, hexlen);
}
return recv_len;
}
Daniel Lee