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
main.cpp
- Committer:
- Daniel_Lee
- Date:
- 2020-02-10
- Revision:
- 47:006469f922f6
- Parent:
- 45:63eba30af193
File content as of revision 47:006469f922f6:
/*
* Copyright (c) 2017 ARM Limited. All rights reserved.
* 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 "mbed.h"
#include "common_functions.h"
#include "UDPSocket.h"
#include "CellularLog.h"
#define UDP 0
#define TCP 1
// Number of retries /
#define RETRY_COUNT 3
NetworkInterface *iface;
// Echo server hostname
const char *host_name = MBED_CONF_APP_ECHO_SERVER_HOSTNAME;
// Echo server port (same for TCP and UDP)
const int port = MBED_CONF_APP_ECHO_SERVER_PORT;
static rtos::Mutex trace_mutex;
#if MBED_CONF_MBED_TRACE_ENABLE
static void trace_wait()
{
trace_mutex.lock();
}
static void trace_release()
{
trace_mutex.unlock();
}
static char time_st[50];
static char* trace_time(size_t ss)
{
snprintf(time_st, 49, "[%08llums]", Kernel::get_ms_count());
return time_st;
}
static void trace_open()
{
mbed_trace_init();
mbed_trace_prefix_function_set( &trace_time );
mbed_trace_mutex_wait_function_set(trace_wait);
mbed_trace_mutex_release_function_set(trace_release);
mbed_cellular_trace::mutex_wait_function_set(trace_wait);
mbed_cellular_trace::mutex_release_function_set(trace_release);
}
static void trace_close()
{
mbed_cellular_trace::mutex_wait_function_set(NULL);
mbed_cellular_trace::mutex_release_function_set(NULL);
mbed_trace_free();
}
#endif // #if MBED_CONF_MBED_TRACE_ENABLE
Thread dot_thread(osPriorityNormal, 512);
void print_function(const char *format, ...)
{
trace_mutex.lock();
va_list arglist;
va_start( arglist, format );
vprintf(format, arglist);
va_end( arglist );
trace_mutex.unlock();
}
void dot_event()
{
while (true) {
ThisThread::sleep_for(4000);
if (iface && iface->get_connection_status() == NSAPI_STATUS_GLOBAL_UP) {
break;
} else {
trace_mutex.lock();
printf(".");
fflush(stdout);
trace_mutex.unlock();
}
}
}
/**
* Connects to the Cellular Network
*/
nsapi_error_t do_connect()
{
nsapi_error_t retcode = NSAPI_ERROR_OK;
uint8_t retry_counter = 0;
while (iface->get_connection_status() != NSAPI_STATUS_GLOBAL_UP) {
retcode = iface->connect();
if (retcode == NSAPI_ERROR_AUTH_FAILURE) {
print_function("\n\nAuthentication Failure. Exiting application\n");
} else if (retcode == NSAPI_ERROR_OK) {
print_function("\n\nConnection Established.\n");
} else if (retry_counter > RETRY_COUNT) {
print_function("\n\nFatal connection failure: %d\n", retcode);
} else {
print_function("\n\nCouldn't connect: %d, will retry\n", retcode);
retry_counter++;
continue;
}
break;
}
return retcode;
}
/**
* Opens a UDP or a TCP socket with the given echo server and performs an echo
* transaction retrieving current.
*/
nsapi_error_t test_send_recv()
{
nsapi_size_or_error_t retcode;
#if MBED_CONF_APP_SOCK_TYPE == TCP
TCPSocket sock;
#else
UDPSocket sock;
#endif
retcode = sock.open(iface);
if (retcode != NSAPI_ERROR_OK) {
#if MBED_CONF_APP_SOCK_TYPE == TCP
print_function("TCPSocket.open() fails, code: %d\n", retcode);
#else
print_function("UDPSocket.open() fails, code: %d\n", retcode);
#endif
return -1;
}
SocketAddress sock_addr;
retcode = iface->gethostbyname(host_name, &sock_addr);
if (retcode != NSAPI_ERROR_OK) {
print_function("Couldn't resolve remote host: %s, code: %d\n", host_name, retcode);
return -1;
}
sock_addr.set_port(port);
sock.set_timeout(15000);
int n = 0;
const char *echo_string = "TEST";
char recv_buf[4];
#if MBED_CONF_APP_SOCK_TYPE == TCP
retcode = sock.connect(sock_addr);
if (retcode < 0) {
print_function("TCPSocket.connect() fails, code: %d\n", retcode);
return -1;
} else {
print_function("TCP: connected with %s server\n", host_name);
}
retcode = sock.send((void*) echo_string, sizeof(echo_string));
if (retcode < 0) {
print_function("TCPSocket.send() fails, code: %d\n", retcode);
return -1;
} else {
print_function("TCP: Sent %d Bytes to %s\n", retcode, host_name);
}
n = sock.recv((void*) recv_buf, sizeof(recv_buf));
#else
retcode = sock.sendto(sock_addr, (void*) echo_string, sizeof(echo_string));
if (retcode < 0) {
print_function("UDPSocket.sendto() fails, code: %d\n", retcode);
return -1;
} else {
print_function("UDP: Sent %d Bytes to %s\n", retcode, host_name);
}
n = sock.recvfrom(&sock_addr, (void*) recv_buf, sizeof(recv_buf));
#endif
sock.close();
if (n > 0) {
print_function("Received from echo server %d Bytes\n", n);
return 0;
}
return -1;
}
int main()
{
DigitalOut TPB23_RESET(A1);
TPB23_RESET = 0; /* 0: Standby 1: Reset */
print_function("\n\nmbed-os-example-cellular\n");
print_function("\n\nBuilt: %s, %s\n", __DATE__, __TIME__);
#ifdef MBED_CONF_NSAPI_DEFAULT_CELLULAR_PLMN
print_function("\n\n[MAIN], plmn: %s\n", (MBED_CONF_NSAPI_DEFAULT_CELLULAR_PLMN ? MBED_CONF_NSAPI_DEFAULT_CELLULAR_PLMN : "NULL"));
#endif
print_function("Establishing connection\n");
#if MBED_CONF_MBED_TRACE_ENABLE
trace_open();
#else
dot_thread.start(dot_event);
#endif // #if MBED_CONF_MBED_TRACE_ENABLE
// sim pin, apn, credentials and possible plmn are taken atuomtically from json when using get_default_instance()
iface = NetworkInterface::get_default_instance();
MBED_ASSERT(iface);
nsapi_error_t retcode = NSAPI_ERROR_NO_CONNECTION;
/* Attempt to connect to a cellular network */
if (do_connect() == NSAPI_ERROR_OK) {
retcode = test_send_recv();
}
if (iface->disconnect() != NSAPI_ERROR_OK) {
print_function("\n\n disconnect failed.\n\n");
}
if (retcode == NSAPI_ERROR_OK) {
print_function("\n\nSuccess. Exiting \n\n");
} else {
print_function("\n\nFailure. Exiting \n\n");
}
#if MBED_CONF_MBED_TRACE_ENABLE
trace_close();
#else
dot_thread.terminate();
#endif // #if MBED_CONF_MBED_TRACE_ENABLE
return 0;
}
// EOF
Daniel Lee