Mbed CE Quectel BC660K-GL EVKIT Example App

Reference application that drives the Quectel BC660K-GL NB-IoT modem (EVKITBC660KGL-1) through the cellular_test library to exercise UDP, TCP, TLS, DTLS and HTTP(S) end-to-end against a configurable echo server.

• MCU target: NUCLEO_L4A6ZG (default), also supported: NUCLEO_L476RG, NUCLEO_L496ZG, NUCLEO_L552ZE_Q, NUCLEO_U575ZI_Q
• Modem driver: bc660kgl/ (Mbed CE cellular framework)
• Mode: AT sockets, module-IP (PPP disabled)

Build

cmake -S . -B build/NUCLEO_L4A6ZG-Debug -G Ninja `
      -DMBED_BOARD=NUCLEO_L4A6ZG -DCMAKE_BUILD_TYPE=Debug
cmake --build build/NUCLEO_L4A6ZG-Debug --target MbedCE_BC660KGL_EVAL_KIT_APP

In VS Code: run task Build MbedCE_BC660KGL_EVAL_KIT_APP, debug with Debug MbedCE_BC660KGL_EVAL_KIT_APP NUCLEO_L4A6ZG Debug (uses ST-LINK_gdbserver on 127.0.0.1:23331, hex auto-loaded).

Operator configuration

Patch mbed_app.json5 under target_overrides."*" for the SIM in use.

1NCE (default)

"nsapi.default-cellular-plmn": "\"26201\"",
"nsapi.default-cellular-apn": "\"iot.1nce.net\"",
"quectel-bc660kgl.provide-default": true,
"quectel-bc660kgl.bands": "\"8\"",

Vodafone

"nsapi.default-cellular-plmn": "\"26202\"",
"nsapi.default-cellular-apn": "\"lpwa.vodafone.iot\"",
"quectel-bc660kgl.provide-default": true,
"quectel-bc660kgl.bands": "\"8,20\"",

Proximus (BE)

"nsapi.default-cellular-apn": "\"m2minternet.proximus.be\"",
"quectel-bc660kgl.provide-default": true,
"quectel-bc660kgl.bands": "\"20\"",

Selecting a test procedure

cellular-test.test-procedure selects exactly one path; only that one compiles in to keep flash low.

value	path
0	UDP echo
1	TCP echo
2	TLS echo
3	fw-TLS echo
4	DTLS echo
5	fw-DTLS echo
6	HTTP GET
7	HTTPS GET

Echo-server endpoints, ports, certificate-verify mode, ping-pong cycles and timeouts live under the cellular-test.* block in mbed_app.json5. See cellular_test for the full parameter list.

Layout

.
├── main.cpp                 // app entry; calls cellular_test
├── mbed_app.json5           // per-target / per-operator config
├── cellular_test/           // protocol echo-test library
├── bc660kgl/                // Quectel BC660K-GL NB-IoT modem driver
└── mbed-os/                 // Mbed OS sources

Related projects

This app is part of a small ecosystem and is designed to work with the iot-test-service, a Dockerised testbed providing UDP / TCP / TLS / DTLS / HTTP / HTTPS echo and mirror endpoints plus a basic .NET management API.