Mbed OS and Pelion Device Management example over WIFI for DISCO_L475VG_IOT01 board

Dependencies:   X_NUCLEO_COMMON ST_INTERFACES

DEPRECATED

This example application is not maintained and not recommended. It uses an old version of Mbed OS, Pelion DM and Arm toolchain. It doesn't work with Mbed Studio.

Please use: https://os.mbed.com/teams/mbed-os-examples/code/mbed-os-example-pelion/

This example is known to work on the following platforms:

DISCO_L475E_IOT01A

Follow the Quick-Start instructions: https://cloud.mbed.com/quick-start

Example functionality

This example showcases the following device functionality:

  • Read onboard temperature and humidity sensors, and report them as Pelion LWM2M resources (see image below).
  • On user button click, increment Pelion LWM2M button resource.
  • Allow the user to change the state of the board LED from Pelion LWM2M led_state resource and PUT request.
  • Uses all onboard sensors and reports them as Pelion LWM2M resources.

/media/uploads/screamer/pelion_st_humidity_reading.png?v=2

Use this example with Mbed CLI

1. Import the application into your desktop:

mbed import https://os.mbed.com/teams/ST/code/pelion-example-disco-iot01

cd pelion-example-disco-iot01

2. Install the CLOUD_SDK_API_KEY

mbed config -G CLOUD_SDK_API_KEY <PELION_DM_API_KEY>

For instructions on how to generate your API key, please see the documentation.

3. Initialize firmware credentials (done once per repository). You can use the following command:

mbed dm init -d "<your company name in Pelion DM>" --model-name "<product model identifier>" -q --force

If above command do not work for your Mbed CLI, please consider upgrading Mbed CLI to version 1.8.x or above.

4. Compile and program:

mbed compile -t <toolchain> -m DISCO_L475VG_IOT01A

(supported toolchains : GCC_ARM / ARM / IAR)

5. You can connect on a virtual terminal/COM port to the platform using:

mbed sterm -b 115200

This should give you an output similar to:

[BOOT] Mbed Bootloader
[BOOT] ARM: 00000000000000000000
[BOOT] OEM: 00000000000000000000
[BOOT] Layout: 0 80096F4
[BOOT] Active firmware integrity check:
[BOOT] SHA256: 0660E360D432225D5251461998FD8617B017098C5F1F90D5FB607BF8C27ED530
[BOOT] Version: 1553615309
[BOOT] Slot 0 is empty
[BOOT] Active firmware up-to-date
[BOOT] Application's start address: 0x8010400
[BOOT] Application's jump address: 0x8011041
[BOOT] Application's stack address: 0x20018000
[BOOT] Forwarding to application...

Starting Simple Pelion Device Management Client example
You can hold the user button during boot to format the storage and change the device identity.

Sensors configuration:
Invalid new address!
HTS221  humidity & temperature    = 0xBC
LPS22HB pressure & temperature    = 0xB1
LIS3MDL magnetometer              = 0x3D
LSM6DSL accelerometer & gyroscope = 0x6A

Connecting to the network using Wifi...
Connected to the network successfully. IP address: 192.168.1.3
Initializing Pelion Device Management Client...
Initialized Pelion Client. Registering...
Registered to Pelion Device Management. Endpoint Name: 0169********************001002d5

ADC temp:     23.0037 C,  vref:      0.3661 V
HTS221 temp:   28.700 C,  humidity:   31.90 %
LPS22HB temp:  29.600 C,  pressure: 1032.01 mbar
LIS3MDL mag:    0.217 x,  -0.284 y,  -0.053 z [gauss]
LSM6DSL acc:    0.005 x,  -0.014 y,   1.029 z [g]
LSM6DSL gyro:   0.910 x,  -0.910 y,   1.120 z [dps]
VL53L0X dist:    1855 mm
Revision:
4:cf7342047b4d
Parent:
1:e86b1cffc402
Child:
6:e0e1e1b93099
--- a/main.cpp	Fri Jul 06 11:43:01 2018 +0200
+++ b/main.cpp	Fri Jul 06 11:44:19 2018 +0200
@@ -1,5 +1,5 @@
 // ----------------------------------------------------------------------------
-// Copyright 2016-2017 ARM Ltd.
+// Copyright 2016-2018 ARM Ltd.
 //
 // SPDX-License-Identifier: Apache-2.0
 //
@@ -17,151 +17,142 @@
 // ----------------------------------------------------------------------------
 
 #include "mbed.h"
-#include "mbed-trace/mbed_trace.h"
-#include "mbed-trace-helper.h"
 #include "simple-mbed-cloud-client.h"
-#include "key-config-manager/kcm_status.h"
-#include "key-config-manager/key_config_manager.h"
 #include "SDBlockDevice.h"
 #include "FATFileSystem.h"
 #include "ISM43362Interface.h"
 
-// Placeholder to hardware that trigger events (timer, button, etc)
-Ticker timer;
+// An event queue is a very useful structure to debounce information between contexts (e.g. ISR and normal threads)
+// This is great because things such as network operations are illegal in ISR, so updating a resource in a button's fall() function is not allowed
+EventQueue eventQueue;
 
-// Placeholder for storage
+// Storage implementation definition, currently using SDBlockDevice (SPI flash, DataFlash, and internal flash are also available)
 SDBlockDevice sd(SPI_MOSI, SPI_MISO, SPI_SCK, SPI_CS);
-FATFileSystem fs("sd");
+FATFileSystem fs("sd", &sd);
+
+// Declaring net interface as a global variable instead of local to avoid stack overflow
+ISM43362Interface net;
 
-// Pointers to the resources that will be created in main_application().
-static MbedCloudClientResource* pattern_ptr;
+// Declaring pointers for access to Mbed Cloud Client resources outside of main()
+MbedCloudClientResource *button_res;
+MbedCloudClientResource *pattern_res;
 
-// Pointer to mbedClient, used for calling close function.
-static SimpleMbedCloudClient *client;
+// This function gets triggered by the timer. It's easy to replace it by an InterruptIn and fall() mode on a real button
+void fake_button_press() {
+    int v = button_res->get_value_int() + 1;
 
-static bool button_pressed = false;
+    button_res->set_value(v);
 
-void button_press() {
-    button_pressed = true;
+    printf("Simulated button clicked %d times\n", v);
 }
 
-void pattern_updated(const char *) {
-    printf("PUT received, new value: %s\n", pattern_ptr->get_value().c_str());
-    // Placeholder for PUT action
+/**
+ * PUT handler
+ * @param resource The resource that triggered the callback
+ * @param newValue Updated value for the resource
+ */
+void pattern_updated(MbedCloudClientResource *resource, m2m::String newValue) {
+    printf("PUT received, new value: %s\n", newValue.c_str());
 }
 
-void blink_callback(void *) {
-    String pattern_str = pattern_ptr->get_value();
-    const char *pattern = pattern_str.c_str();
-    printf("POST received. LED pattern = %s\n", pattern);
-    // Placeholder for POST action
-    // The pattern is something like 500:200:500, so parse that.
-}
+/**
+ * POST handler
+ * @param resource The resource that triggered the callback
+ * @param buffer If a body was passed to the POST function, this contains the data.
+ *               Note that the buffer is deallocated after leaving this function, so copy it if you need it longer.
+ * @param size Size of the body
+ */
+void blink_callback(MbedCloudClientResource *resource, const uint8_t *buffer, uint16_t size) {
+    printf("POST received. Going to blink LED pattern: %s\n", pattern_res->get_value().c_str());
+
+    static DigitalOut augmentedLed(LED1); // LED that is used for blinking the pattern
 
-void button_callback(const M2MBase& object, const NoticationDeliveryStatus status)
-{
-    printf("Button notification. Callback: (%s)\n", object.uri_path());
-    // Placeholder for GET
+    // Parse the pattern string, and toggle the LED in that pattern
+    string s = std::string(pattern_res->get_value().c_str());
+    size_t i = 0;
+    size_t pos = s.find(':');
+    while (pos != string::npos) {
+        wait_ms(atoi(s.substr(i, pos - i).c_str()));
+        augmentedLed = !augmentedLed;
+
+        i = ++pos;
+        pos = s.find(':', pos);
+
+        if (pos == string::npos) {
+            wait_ms(atoi(s.substr(i, s.length()).c_str()));
+            augmentedLed = !augmentedLed;
+        }
+    }
 }
 
-
-int main(void)
-{
-    // Requires DAPLink 245+ (https://github.com/ARMmbed/DAPLink/pull/364)
-    // Older versions: workaround to prevent possible deletion of credentials:
-    wait(2);
-
-    // Misc OS setup
-    srand(time(NULL));
+/**
+ * Notification callback handler
+ * @param resource The resource that triggered the callback
+ * @param status The delivery status of the notification
+ */
+void button_callback(MbedCloudClientResource *resource, const NoticationDeliveryStatus status) {
+    printf("Button notification, status %s (%d)\n", MbedCloudClientResource::delivery_status_to_string(status), status);
+}
 
-    // Placeholder for network
-    printf("Start Simple Mbed Cloud Client\n");
-    ISM43362Interface net(MBED_CONF_APP_WIFI_SPI_MOSI, MBED_CONF_APP_WIFI_SPI_MISO, MBED_CONF_APP_WIFI_SPI_SCLK, MBED_CONF_APP_WIFI_SPI_NSS, MBED_CONF_APP_WIFI_RESET, MBED_CONF_APP_WIFI_DATAREADY, MBED_CONF_APP_WIFI_WAKEUP, false);
-
+/**
+ * Registration callback handler
+ * @param endpoint Information about the registered endpoint such as the name (so you can find it back in portal)
+ */
+void registered(const ConnectorClientEndpointInfo *endpoint) {
+    printf("Connected to Mbed Cloud. Endpoint Name: %s\n", endpoint->internal_endpoint_name.c_str());
+}
 
-    // Initialize SD card
-    int status = sd.init();
-    if (status != BD_ERROR_OK) {
-        printf("Failed to init SD card\r\n");
+int main(void) {
+    printf("Starting Simple Mbed Cloud Client example\n");
+    printf("Connecting to the network using Wifi...\n");
+
+    // Connect to the internet (DHCP is expected to be on)
+    nsapi_error_t status = net.connect(MBED_CONF_APP_WIFI_SSID, MBED_CONF_APP_WIFI_PASSWORD, (strlen(MBED_CONF_APP_WIFI_PASSWORD) > 1) ? NSAPI_SECURITY_WPA_WPA2 : NSAPI_SECURITY_NONE);
+
+    if (status != 0) {
+        printf("Connecting to the network failed %d!\n", status);
         return -1;
     }
 
-    // Mount the file system (reformatting on failure)
-    status = fs.mount(&sd);
-    if (status) {
-        printf("Failed to mount FAT file system, reformatting...\r\n");
-        status = fs.reformat(&sd);
-        if (status) {
-            printf("Failed to reformat FAT file system\r\n");
-            return -1;
-        } else {
-            printf("Reformat and mount complete\r\n");
-        }
-    }
-
-    printf("Connecting to the network using Wifi...\n");
+    printf("Connected to the network successfully. IP address: %s\n", net.get_ip_address());
 
-    status = net.connect(MBED_CONF_APP_WIFI_SSID, MBED_CONF_APP_WIFI_PASSWORD, (strlen(MBED_CONF_APP_WIFI_PASSWORD) > 1) ? NSAPI_SECURITY_WPA_WPA2 : NSAPI_SECURITY_NONE);
-    if (status) {
-        printf("Connection to Network Failed %d!\n", status);
-        return -1;
-    } else {
-        const char *ip_addr  = net.get_ip_address();
-        printf("Connected successfully\n");
-        printf("IP address %s\n", ip_addr);
-    }
-
-    SimpleMbedCloudClient mbedClient(&net);
-    // Save pointer to mbedClient so that other functions can access it.
-    client = &mbedClient;
-
-    status = mbedClient.init();
-    if (status) {
-        printf("FAILED\r\n");
+    // SimpleMbedCloudClient handles registering over LwM2M to Mbed Cloud
+    SimpleMbedCloudClient client(&net, &sd, &fs);
+    int client_status = client.init();
+    if (client_status != 0) {
+        printf("Initializing Mbed Cloud Client failed (%d)\n", client_status);
         return -1;
     }
 
-    printf("Client initialized\r\n");
+    // Creating resources, which can be written or read from the cloud
+    button_res = client.create_resource("3200/0/5501", "button_count");
+    button_res->set_value(0);
+    button_res->methods(M2MMethod::GET);
+    button_res->observable(true);
+    button_res->attach_notification_callback(button_callback);
 
-    // Mbed Cloud Client resource setup
-    MbedCloudClientResource *button = mbedClient.create_resource("3200/0/5501", "button_resource");
-    button->set_value("0");
-    button->methods(M2MMethod::GET);
-    button->observable(true);
-    button->attach_notification_callback(button_callback);
+    pattern_res = client.create_resource("3201/0/5853", "blink_pattern");
+    pattern_res->set_value("500:500:500:500:500:500:500:500");
+    pattern_res->methods(M2MMethod::GET | M2MMethod::PUT);
+    pattern_res->attach_put_callback(pattern_updated);
 
-    MbedCloudClientResource *pattern = mbedClient.create_resource("3201/0/5853", "pattern_resource");
-    pattern->set_value("500:500:500:500");
-    pattern->methods(M2MMethod::GET | M2MMethod::PUT);
-    pattern->attach_put_callback(pattern_updated);
-    pattern_ptr = pattern;
+    MbedCloudClientResource *blink_res = client.create_resource("3201/0/5850", "blink_action");
+    blink_res->methods(M2MMethod::POST);
+    blink_res->attach_post_callback(blink_callback);
+
+    printf("Initialized Mbed Cloud Client. Registering...\n");
 
-    MbedCloudClientResource *blink = mbedClient.create_resource("3201/0/5850", "blink_resource");
-    blink->methods(M2MMethod::POST);
-    blink->attach_post_callback(blink_callback);
+    // Callback that fires when registering is complete
+    client.on_registered(&registered);
 
-    mbedClient.register_and_connect();
-
-    // Wait for client to finish registering
-    while (!mbedClient.is_client_registered()) {
-        wait_ms(100);
-    }
+    // Register with Mbed Cloud
+    client.register_and_connect();
 
     // Placeholder for callback to update local resource when GET comes.
-    timer.attach(&button_press, 5.0);
-
-    // Check if client is registering or registered, if true sleep and repeat.
-    while (mbedClient.is_register_called()) {
-        static int button_count = 0;
-        wait_ms(100);
+    // The timer fires on an interrupt context, but debounces it to the eventqueue, so it's safe to do network operations
+    Ticker timer;
+    timer.attach(eventQueue.event(&fake_button_press), 5.0);
 
-        if (button_pressed) {
-            button_pressed = false;
-            printf("Simulated button clicked %d times\r\n", ++button_count);
-            button->set_value(button_count);
-        }
-    }
-
-    // Client unregistered, exit program.
-    return 0;
+    // You can easily run the eventQueue in a separate thread if required
+    eventQueue.dispatch_forever();
 }