FAQ-Link IoT Edge(IoT Edge)-阿里云帮助中心

This topic describes common problems and solutions for driver development.

device_cb parameter in the leda_register_and_online_by_device_name(const char *product_key, const char *device_name, leda_device_callback_t *device_cb, void *usr_data) function?
A:

It receives service requests for the device from the cloud or other edge applications. These requests include retrieving device properties, setting device properties, and calling device services.

typedef struct leda_device_callback
{

   ...
   int  service_output_max_count;   /* The maximum length of the device service callback result array */
} leda_device_callback_t;

What does the service_output_max_count field mean?

It sets the maximum length of the output_data array for the call_service_cb callback.

worker_thread_nums parameter used for in the leda_init(const char *module_name, int worker_thread_nums) function?
A:

It initializes the driver's thread pool. This pool handles device requests from the cloud or edge applications. Set the size of the pool based on the number of connected devices.
leda_register_and_online_by_device_name and leda_register_and_online_by_local_name?
A:
- by_device_name: The `device_name` used for registration must match the name specified when the device was created in the Alibaba Cloud IoT Platform.
- by_local_name: The `device_name` used for registration can be a custom name.
  Note For devices that have the same ProductKey, you must use only one of these functions for registration. Do not use both the by_device_name and by_local_name functions for the same ProductKey.
The device is online and the driver logs show that data is reported correctly, but the data is not updated in the IoT Platform console.
A:

Confirm that message routing is configured in the IoT Platform console. For more information, see Set up message routing.