Generic Attribute Profile (gatt)#

The commands and events in this class are used to browse and manage attributes in a remote GATT server.

gatt commands#

gatt_discover_characteristics#

Discover all characteristics of a GATT service from a remote GATT database. This command generates a unique gatt_characteristic event for every discovered characteristic. Received gatt_procedure_completed event indicates that this GATT procedure was successfully completed or failed with an error.

C API#

/* Function */  
struct gecko_msg_gatt_discover_characteristics_rsp_t *gecko_cmd_gatt_discover_characteristics(uint8 connection, uint32 service);  
  
/* Response id */  
gecko_rsp_gatt_discover_characteristics_id  
  
/* Response structure */  
struct gecko_msg_gatt_discover_characteristics_rsp_t  
{  
  uint16 result;  
}  

Command Parameters (for BGAPI headers refer to link)#

This value is normally received from the gatt_service event.

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes

Events generated#

gatt_discover_characteristics_by_uuid#

Discover all characteristics of a GATT service in a remote GATT database having the specified UUID. This command generates a unique gatt_characteristic event for every discovered characteristic having the specified UUID. Received gatt_procedure_completed event indicates that this GATT procedure was successfully completed or failed with an error.

C API#

/* Function */  
struct gecko_msg_gatt_discover_characteristics_by_uuid_rsp_t *gecko_cmd_gatt_discover_characteristics_by_uuid(uint8 connection, uint32 service, uint8 uuid_len, const uint8 *uuid_data);  
  
/* Response id */  
gecko_rsp_gatt_discover_characteristics_by_uuid_id  
  
/* Response structure */  
struct gecko_msg_gatt_discover_characteristics_by_uuid_rsp_t  
{  
  uint16 result;  
}  

Command Parameters (for BGAPI headers refer to link)#

This value is normally received from the gatt_service event.

uint8 | uuid_len | Array length.
uint8array | uuid_data | Characteristic UUID in little endian format

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes

Events generated#

gatt_discover_descriptors#

Discover all descriptors of a GATT characteristic in a remote GATT database. It generates a unique gatt_descriptor event for every discovered descriptor. Received gatt_procedure_completed event indicates that this GATT procedure has successfully completed or failed with an error.

C API#

/* Function */  
struct gecko_msg_gatt_discover_descriptors_rsp_t *gecko_cmd_gatt_discover_descriptors(uint8 connection, uint16 characteristic);  
  
/* Response id */  
gecko_rsp_gatt_discover_descriptors_id  
  
/* Response structure */  
struct gecko_msg_gatt_discover_descriptors_rsp_t  
{  
  uint16 result;  
}  

Command Parameters (for BGAPI headers refer to link)#

This value is normally received from the gatt_characteristic event.

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes

Events generated#

gatt_discover_primary_services#

Discover all primary services of a remote GATT database. This command generates a unique gatt_service event for every discovered primary service. Received gatt_procedure_completed event indicates that this GATT procedure has successfully completed or failed with an error.

C API#

/* Function */  
struct gecko_msg_gatt_discover_primary_services_rsp_t *gecko_cmd_gatt_discover_primary_services(uint8 connection);  
  
/* Response id */  
gecko_rsp_gatt_discover_primary_services_id  
  
/* Response structure */  
struct gecko_msg_gatt_discover_primary_services_rsp_t  
{  
  uint16 result;  
}  

Command Parameters (for BGAPI headers refer to link)#

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes

Events generated#

gatt_discover_primary_services_by_uuid#

Discover primary services with the specified UUID in a remote GATT database. This command generates unique gatt_service event for every discovered primary service. Received gatt_procedure_completed event indicates that this GATT procedure was successfully completed or failed with an error.

C API#

/* Function */  
struct gecko_msg_gatt_discover_primary_services_by_uuid_rsp_t *gecko_cmd_gatt_discover_primary_services_by_uuid(uint8 connection, uint8 uuid_len, const uint8 *uuid_data);  
  
/* Response id */  
gecko_rsp_gatt_discover_primary_services_by_uuid_id  
  
/* Response structure */  
struct gecko_msg_gatt_discover_primary_services_by_uuid_rsp_t  
{  
  uint16 result;  
}  

Command Parameters (for BGAPI headers refer to link)#

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes

Events generated#

gatt_execute_characteristic_value_write#

Commit or cancel previously queued writes to a long characteristic of a remote GATT server. Writes are sent to the queue with prepare_characteristic_value_write command. Content, offset, and length of queued values are validated by this procedure. A received gatt_procedure_completed event indicates that all data was written successfully or that an error response was received.

C API#

/* Function */  
struct gecko_msg_gatt_execute_characteristic_value_write_rsp_t *gecko_cmd_gatt_execute_characteristic_value_write(uint8 connection, uint8 flags);  
  
/* Response id */  
gecko_rsp_gatt_execute_characteristic_value_write_id  
  
/* Response structure */  
struct gecko_msg_gatt_execute_characteristic_value_write_rsp_t  
{  
  uint16 result;  
}  

Command Parameters (for BGAPI headers refer to link)#

• 0: cancel

• 1: commit

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes

Events generated#

gatt_find_included_services#

Find the services that are included by a service in a remote GATT database. This command generates a unique gatt_service event for each included service. The received gatt_procedure_completed event indicates that this GATT procedure was successfully completed or failed with an error.

C API#

/* Function */  
struct gecko_msg_gatt_find_included_services_rsp_t *gecko_cmd_gatt_find_included_services(uint8 connection, uint32 service);  
  
/* Response id */  
gecko_rsp_gatt_find_included_services_id  
  
/* Response structure */  
struct gecko_msg_gatt_find_included_services_rsp_t  
{  
  uint16 result;  
}  

Command Parameters (for BGAPI headers refer to link)#

This value is normally received from the gatt_service event.

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes

Events generated#

gatt_prepare_characteristic_value_reliable_write#

Add a characteristic value to the write queue of a remote GATT server and verifies whether the value was correctly received by the server. Received gatt_procedure_completed event indicates that this GATT procedure was successfully completed or failed with an error. Specifically, error code 0x0194 (data_corrupted) will be returned if the value received from the GATT server's response fails to pass the reliable write verification. At most ATT_MTU - 5 amount of data can be sent at one time. Writes are executed or canceled with the execute_characteristic_value_write command. Whether the writes succeed or not is indicated in the response of the execute_characteristic_value_write command.

C API#

/* Function */  
struct gecko_msg_gatt_prepare_characteristic_value_reliable_write_rsp_t *gecko_cmd_gatt_prepare_characteristic_value_reliable_write(uint8 connection, uint16 characteristic, uint16 offset, uint8 value_len, const uint8 *value_data);  
  
/* Response id */  
gecko_rsp_gatt_prepare_characteristic_value_reliable_write_id  
  
/* Response structure */  
struct gecko_msg_gatt_prepare_characteristic_value_reliable_write_rsp_t  
{  
  uint16 result;  
  uint16 sent_len;  
}  

Command Parameters (for BGAPI headers refer to link)#

This value is normally received from the gatt_characteristic event.

uint16 | offset | Offset of the characteristic value
uint8 | value_len | Array length.
uint8array | value_data | Value to write into the specified characteristic of the remote GATT database

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes
uint16 | sent_len | The length of data sent to the remote GATT server

Events generated#

gatt_prepare_characteristic_value_write#

Add a characteristic value to the write queue of a remote GATT server. It can be used when long attributes need to be written or a set of values needs to be written atomically. At most ATT_MTU - 5 amount of data can be sent at one time. Writes are executed or canceled with the execute_characteristic_value_write command. Whether the writes succeed or not is indicated in the response of the execute_characteristic_value_write command.

In all use cases where the amount of data to transfer fits into the BGAPI payload, use the command gatt_write_characteristic_value to write long values because it transparently performs the prepare_write and execute_write commands.

C API#

/* Function */  
struct gecko_msg_gatt_prepare_characteristic_value_write_rsp_t *gecko_cmd_gatt_prepare_characteristic_value_write(uint8 connection, uint16 characteristic, uint16 offset, uint8 value_len, const uint8 *value_data);  
  
/* Response id */  
gecko_rsp_gatt_prepare_characteristic_value_write_id  
  
/* Response structure */  
struct gecko_msg_gatt_prepare_characteristic_value_write_rsp_t  
{  
  uint16 result;  
  uint16 sent_len;  
}  

Command Parameters (for BGAPI headers refer to link)#

This value is normally received from the gatt_characteristic event.

uint16 | offset | Offset of the characteristic value
uint8 | value_len | Array length.
uint8array | value_data | Value to write into the specified characteristic of the remote GATT database

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes
uint16 | sent_len | The length of data sent to the remote GATT server

Events generated#

gatt_read_characteristic_value#

Read the value of a characteristic from a remote GATT database. A single gatt_characteristic_value event is generated if the characteristic value fits in one ATT PDU. Otherwise, more than one gatt_characteristic_value event is generated because the firmware will automatically use the Read Long Characteristic Values procedure. A received gatt_procedure_completed event indicates that all data was read successfully or that an error response was received.

Note that the GATT client does not verify if the requested attribute is a characteristic value. Therefore, before calling this command, ensure that the attribute handle is for a characteristic value, for example, by performing characteristic discovery.

C API#

/* Function */  
struct gecko_msg_gatt_read_characteristic_value_rsp_t *gecko_cmd_gatt_read_characteristic_value(uint8 connection, uint16 characteristic);  
  
/* Response id */  
gecko_rsp_gatt_read_characteristic_value_id  
  
/* Response structure */  
struct gecko_msg_gatt_read_characteristic_value_rsp_t  
{  
  uint16 result;  
}  

Command Parameters (for BGAPI headers refer to link)#

This value is normally received from the gatt_characteristic event.

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes

Events generated#

gatt_read_characteristic_value_by_uuid#

Read characteristic values of a service from a remote GATT database by giving the UUID of the characteristic and the handle of the service containing this characteristic. If multiple characteristic values are received in one ATT PDU, then one gatt_characteristic_value event is generated for each value. If the first characteristic value does not fit in one ATT PDU, the firmware automatically uses the Read Long Characteristic Values procedure and generate more gatt_characteristic_value events until the value has been completely read. A received gatt_procedure_completed event indicates that all data was read successfully or that an error response was received.

C API#

/* Function */  
struct gecko_msg_gatt_read_characteristic_value_by_uuid_rsp_t *gecko_cmd_gatt_read_characteristic_value_by_uuid(uint8 connection, uint32 service, uint8 uuid_len, const uint8 *uuid_data);  
  
/* Response id */  
gecko_rsp_gatt_read_characteristic_value_by_uuid_id  
  
/* Response structure */  
struct gecko_msg_gatt_read_characteristic_value_by_uuid_rsp_t  
{  
  uint16 result;  
}  

Command Parameters (for BGAPI headers refer to link)#

This value is normally received from the gatt_service event.

uint8 | uuid_len | Array length.
uint8array | uuid_data | Characteristic UUID in little endian format

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes

Events generated#

gatt_read_characteristic_value_from_offset#

Read a partial characteristic value with a specified offset and maximum length from a remote GATT database. It is equivalent to gatt_read_characteristic_value if both the offset and maximum length parameters are 0. A single gatt_characteristic_value event is generated if the value to read fits in one ATT PDU. Otherwise, more than one gatt_characteristic_value events are generated because the firmware will automatically use the Read Long Characteristic Values procedure. A received gatt_procedure_completed event indicates that all data was read successfully or that an error response was received.

C API#

/* Function */  
struct gecko_msg_gatt_read_characteristic_value_from_offset_rsp_t *gecko_cmd_gatt_read_characteristic_value_from_offset(uint8 connection, uint16 characteristic, uint16 offset, uint16 maxlen);  
  
/* Response id */  
gecko_rsp_gatt_read_characteristic_value_from_offset_id  
  
/* Response structure */  
struct gecko_msg_gatt_read_characteristic_value_from_offset_rsp_t  
{  
  uint16 result;  
}  

Command Parameters (for BGAPI headers refer to link)#

This value is normally received from the gatt_characteristic event.

uint16 | offset | Offset of the characteristic value
uint16 | maxlen | Maximum bytes to read. If this parameter is 0, all characteristic values starting at a given offset will be read.

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes

Events generated#

gatt_read_descriptor_value#

Read the descriptor value of a characteristic in a remote GATT database. A single gatt_descriptor_value event is generated if the descriptor value fits in one ATT PDU. Otherwise, more than one gatt_descriptor_value events are generated because the firmware automatically uses the Read Long Characteristic Values procedure. A received gatt_procedure_completed event indicates that all data was read successfully or that an error response was received.

C API#

/* Function */  
struct gecko_msg_gatt_read_descriptor_value_rsp_t *gecko_cmd_gatt_read_descriptor_value(uint8 connection, uint16 descriptor);  
  
/* Response id */  
gecko_rsp_gatt_read_descriptor_value_id  
  
/* Response structure */  
struct gecko_msg_gatt_read_descriptor_value_rsp_t  
{  
  uint16 result;  
}  

Command Parameters (for BGAPI headers refer to link)#

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes

Events generated#

gatt_read_multiple_characteristic_values#

Read values of multiple characteristics from a remote GATT database at once. The GATT server returns values in one ATT PDU as the response. If the total set of values is greater than (ATT_MTU - 1) bytes in length, only the first (ATT_MTU - 1) bytes are included. A single gatt_characteristic_value event is generated, in which the characteristic is set to 0 and data in the value parameter is a concatenation of characteristic values in the order they were requested. The received gatt_procedure_completed event indicates either that this GATT procedure was successfully completed or failed with an error.

Use this command only for characteristics values that have a known fixed size, except the last one that could have variable length.

When the remote GATT server is from Silicon Labs Bluetooth stack, the server returns ATT Invalid PDU (0x04) if this command only reads one characteristic value. The server returns ATT Application Error 0x80 if this command reads the value of a user-type characteristic.

C API#

/* Function */  
struct gecko_msg_gatt_read_multiple_characteristic_values_rsp_t *gecko_cmd_gatt_read_multiple_characteristic_values(uint8 connection, uint8 characteristic_list_len, const uint8 *characteristic_list_data);  
  
/* Response id */  
gecko_rsp_gatt_read_multiple_characteristic_values_id  
  
/* Response structure */  
struct gecko_msg_gatt_read_multiple_characteristic_values_rsp_t  
{  
  uint16 result;  
}  

Command Parameters (for BGAPI headers refer to link)#

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes

Events generated#

gatt_send_characteristic_confirmation#

Send a confirmation to a remote GATT server after receiving a characteristic indication. The gatt_characteristic_value event carries the att_opcode containing handle_value_indication (0x1d), which reveals that an indication has been received and must be confirmed with this command. The confirmation needs to be sent within 30 seconds, otherwise further GATT transactions are not allowed by the remote side.

C API#

/* Function */  
struct gecko_msg_gatt_send_characteristic_confirmation_rsp_t *gecko_cmd_gatt_send_characteristic_confirmation(uint8 connection);  
  
/* Response id */  
gecko_rsp_gatt_send_characteristic_confirmation_id  
  
/* Response structure */  
struct gecko_msg_gatt_send_characteristic_confirmation_rsp_t  
{  
  uint16 result;  
}  

Command Parameters (for BGAPI headers refer to link)#

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes

gatt_set_characteristic_notification#

Enable or disable the notifications and indications sent from a remote GATT server. This procedure discovers a characteristic client configuration descriptor and writes the related configuration flags to a remote GATT database. A received gatt_procedure_completed event indicates that this GATT procedure was successfully completed or that it failed with an error.

C API#

/* Function */  
struct gecko_msg_gatt_set_characteristic_notification_rsp_t *gecko_cmd_gatt_set_characteristic_notification(uint8 connection, uint16 characteristic, uint8 flags);  
  
/* Response id */  
gecko_rsp_gatt_set_characteristic_notification_id  
  
/* Response structure */  
struct gecko_msg_gatt_set_characteristic_notification_rsp_t  
{  
  uint16 result;  
}  

Command Parameters (for BGAPI headers refer to link)#

This value is normally received from the gatt_characteristic event.

uint8 | flags | Characteristic client configuration flags

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes

Events generated#

gatt_set_max_mtu#

Set the maximum size of ATT Message Transfer Units (MTU). Functionality is the same as gatt_server_set_max_mtu and this setting applies to both GATT client and server. If the given value is too large according to the maximum BGAPI payload size, the system will select the maximum possible value as the maximum ATT_MTU. If maximum ATT_MTU is larger than 23, the GATT client in the stack will automatically send an MTU exchange request after a Bluetooth connection has been established.

C API#

/* Function */  
struct gecko_msg_gatt_set_max_mtu_rsp_t *gecko_cmd_gatt_set_max_mtu(uint16 max_mtu);  
  
/* Response id */  
gecko_rsp_gatt_set_max_mtu_id  
  
/* Response structure */  
struct gecko_msg_gatt_set_max_mtu_rsp_t  
{  
  uint16 result;  
  uint16 max_mtu;  
}  

Command Parameters (for BGAPI headers refer to link)#

• Range: 23 to 250

Default: 247

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes
uint16 | max_mtu | The maximum ATT_MTU selected by the system if this command succeeds

gatt_write_characteristic_value#

Write the value of a characteristic in a remote GATT database. If the given value does not fit in one ATT PDU, "write long" GATT procedure is used automatically. Received gatt_procedure_completed event indicates that all data was written successfully or that an error response was received.

C API#

/* Function */  
struct gecko_msg_gatt_write_characteristic_value_rsp_t *gecko_cmd_gatt_write_characteristic_value(uint8 connection, uint16 characteristic, uint8 value_len, const uint8 *value_data);  
  
/* Response id */  
gecko_rsp_gatt_write_characteristic_value_id  
  
/* Response structure */  
struct gecko_msg_gatt_write_characteristic_value_rsp_t  
{  
  uint16 result;  
}  

Command Parameters (for BGAPI headers refer to link)#

This value is normally received from the gatt_characteristic event.

uint8 | value_len | Array length.
uint8array | value_data | Characteristic value

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes

Events generated#

gatt_write_characteristic_value_without_response#

Write the value of a characteristic in a remote GATT server. It does not generate an event. All failures on the server are ignored silently. For example, if an error is generated in the remote GATT server and the given value is not written into the database, no error message will be reported to the local GATT client. Note that this command can't be used to write long values. At most ATT_MTU - 3 amount of data can be sent once.

C API#

/* Function */  
struct gecko_msg_gatt_write_characteristic_value_without_response_rsp_t *gecko_cmd_gatt_write_characteristic_value_without_response(uint8 connection, uint16 characteristic, uint8 value_len, const uint8 *value_data);  
  
/* Response id */  
gecko_rsp_gatt_write_characteristic_value_without_response_id  
  
/* Response structure */  
struct gecko_msg_gatt_write_characteristic_value_without_response_rsp_t  
{  
  uint16 result;  
  uint16 sent_len;  
}  

Command Parameters (for BGAPI headers refer to link)#

This value is normally received from the gatt_characteristic event.

uint8 | value_len | Array length.
uint8array | value_data | Characteristic value

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes
uint16 | sent_len | The length of data sent to the remote GATT server

gatt_write_descriptor_value#

Write the value of a characteristic descriptor in a remote GATT database. If the given value does not fit in one ATT PDU, "write long" GATT procedure is used automatically. Received gatt_procedure_completed event indicates either that all data was written successfully or that an error response was received.

C API#

/* Function */  
struct gecko_msg_gatt_write_descriptor_value_rsp_t *gecko_cmd_gatt_write_descriptor_value(uint8 connection, uint16 descriptor, uint8 value_len, const uint8 *value_data);  
  
/* Response id */  
gecko_rsp_gatt_write_descriptor_value_id  
  
/* Response structure */  
struct gecko_msg_gatt_write_descriptor_value_rsp_t  
{  
  uint16 result;  
}  

Command Parameters (for BGAPI headers refer to link)#

Response Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes

Events generated#

gatt events#

gatt_mtu_exchanged#

Indicates that an ATT_MTU exchange procedure is completed. The mtu parameter describes new MTU size. MTU size 23 is used before this event is received.

C API#

/* event id*/  
gecko_evt_gatt_mtu_exchanged_id  
  
/* event structure*/  
struct gecko_msg_gatt_mtu_exchanged_evt_t  
{  
  uint8 connection;  
  uint16 mtu;  
}  

Event Parameters (for BGAPI headers refer to link)#

gatt_service#

Indicate that a GATT service in the remote GATT database was discovered. This event is generated after issuing either the gatt_discover_primary_services or gatt_discover_primary_services_by_uuid command.

C API#

/* event id*/  
gecko_evt_gatt_service_id  
  
/* event structure*/  
struct gecko_msg_gatt_service_evt_t  
{  
  uint8 connection;  
  uint32 service;  
  uint8array uuid;  
}  

Event Parameters (for BGAPI headers refer to link)#

gatt_characteristic#

Indicates that a GATT characteristic in the remote GATT database was discovered. This event is generated after issuing either the gatt_discover_characteristics or gatt_discover_characteristics_by_uuid command.

C API#

/* event id*/  
gecko_evt_gatt_characteristic_id  
  
/* event structure*/  
struct gecko_msg_gatt_characteristic_evt_t  
{  
  uint8 connection;  
  uint16 characteristic;  
  uint8 properties;  
  uint8array uuid;  
}  

Event Parameters (for BGAPI headers refer to link)#

gatt_descriptor#

Indicates that a GATT characteristic descriptor in the remote GATT database was discovered. It is generated after issuing the gatt_discover_descriptors command.

C API#

/* event id*/  
gecko_evt_gatt_descriptor_id  
  
/* event structure*/  
struct gecko_msg_gatt_descriptor_evt_t  
{  
  uint8 connection;  
  uint16 descriptor;  
  uint8array uuid;  
}  

Event Parameters (for BGAPI headers refer to link)#

gatt_characteristic_value#

Indicates that the value of one or several characteristics in the remote GATT server was received. It is triggered by several commands: gatt_read_characteristic_value, gatt_read_characteristic_value_from_offset, gatt_read_characteristic_value_by_uuid, gatt_read_multiple_characteristic_values; and when the remote GATT server sends indications or notifications after enabling notifications with gatt_set_characteristic_notification. The parameter att_opcode indicates which type of GATT transaction triggered this event. In particular, if the att_opcode type is handle_value_indication (0x1d), the application needs to confirm the indication with gatt_send_characteristic_confirmation.

C API#

/* event id*/  
gecko_evt_gatt_characteristic_value_id  
  
/* event structure*/  
struct gecko_msg_gatt_characteristic_value_evt_t  
{  
  uint8 connection;  
  uint16 characteristic;  
  [uint8 att_opcode](gatt#enum_gatt_att_opcode);  
  uint16 offset;  
  uint8array value;  
}  

Event Parameters (for BGAPI headers refer to link)#

This value is normally received from the gatt_characteristic event.

uint8 | att_opcode | Attribute opcode, which indicates the GATT transaction used
uint16 | offset | Value offset
uint8array | value | Characteristic value

gatt_descriptor_value#

Indicates that the value of a descriptor in the remote GATT server was received. This event is generated by the gatt_read_descriptor_value command.

C API#

/* event id*/  
gecko_evt_gatt_descriptor_value_id  
  
/* event structure*/  
struct gecko_msg_gatt_descriptor_value_evt_t  
{  
  uint8 connection;  
  uint16 descriptor;  
  uint16 offset;  
  uint8array value;  
}  

Event Parameters (for BGAPI headers refer to link)#

gatt_procedure_completed#

Indicates that the current GATT procedure was completed successfully or that it failed with an error. All GATT commands excluding gatt_write_characteristic_value_without_response and gatt_send_characteristic_confirmation will trigger this event. As a result, the application must wait for this event before issuing another GATT command (excluding the two aforementioned exceptions).

C API#

/* event id*/  
gecko_evt_gatt_procedure_completed_id  
  
/* event structure*/  
struct gecko_msg_gatt_procedure_completed_evt_t  
{  
  uint8 connection;  
  uint16 result;  
}  

Event Parameters (for BGAPI headers refer to link)#

• 0: success

• Non-zero: an error has occurred

For other values see Error codes

gatt enumerations#

gatt_att_opcode#

These values indicate which attribute request or response has caused the event.

Enumerations#

gatt_client_config_flag#

These values define whether the client is to receive notifications or indications from a remote GATT server.

Enumerations#

gatt_execute_write_flag#

These values define whether the GATT server is to cancel all queued writes or commit all queued writes to a remote database.

Enumerations#