Embedded MQTT client#

rsi_emb_mqtt_client_init#

int32_t rsi_emb_mqtt_client_init (int8_t * server_ip, uint32_t server_port, uint32_t client_port, uint16_t flags, uint16_t keep_alive_interval, int8_t * clientid, int8_t * username, int8_t * password)

Create MQTT objects. TCP level connection happens in this API. This is a blocking API.

• rsi_config_ipaddress() API needs to be called before this API.

Returns

• 0 - Success
  

• Negative Value - Failure (Possible Error Codes - 0xfffffffe, 0xfffffffd, 0xfffffffc, 0xfffffffb, 0xffffffe0)
  

Note

• RSI_EMB_MQTT_KEEPALIVE_RETRIES - Configures the MQTT Keep-alive retries in case the MQTT Ping response is not received from the MQTT broker within the command acknowledgement time (35 seconds) during the MQTT Keep-alive process.

• In this case, the device notifies the application through RSI_WLAN_NWK_EMB_MQTT_KEEPALIVE_TIMEOUT_CB callback, if it is registered. The MQTT Keep Alive retries happen every 35 seconds until MQTT Ping response is received for MQTT Ping request or until all the MQTT Keep Alive retries elapse.This can be configured in rsi_wlan_config.h.

• This is an optional parameter. If not configured, the default value is 0. In this case, device will not perform MQTT Keep Alive retries, however the MQTT Keep Alive process keeps happening (until MQTT connection is terminated) every Keep Alive Time period configured by the host.
  

• Precondition - rsi_config_ipaddress() API needs to be called before this API.

• Refer to Error Codes for the description of above error codes.

rsi_emb_mqtt_connect#

int32_t rsi_emb_mqtt_connect (uint8_t mqtt_flags, int8_t * will_topic, uint16_t will_message_len, int8_t * will_message)

Connect to MQTT Server/Broker. MQTT level connection happens in this API. This is a blocking API.

Returns

• 0 - Success
  

• Negative Value - Failure (Possible Error Codes - 0xfffffffd, 0xfffffffc, 0xfffffffb, 0xffffffe0)
  

Note

• Precondition - rsi_emb_mqtt_client_init() API needs to be called before this API.

• will_topic and will_message are not supported and should be NULL.

• For connecting Embedded MQTT over SSL :
  Enable TCP_IP_FEAT_SSL in Opermode parameters as here
  #define RSI_TCP_IP_FEATURE_BIT_MAP (TCP_IP_FEAT_DHCPV4_CLIENT | TCP_IP_FEAT_SSL | TCP_IP_FEAT_DNS_CLIENT).
  Load the related SSL Certificates in the module using rsi_wlan_set_certificate() API.

• Refer to Error Codes for the description of above error codes.
  

• Length of the topic Length should not exceed 200 bytes excluding NULL termination character.

rsi_emb_mqtt_publish#

int32_t rsi_emb_mqtt_publish (int8_t * topic, rsi_mqtt_pubmsg_t * publish_msg)

Publish the given message on the topic specified. This is a blocking API.

Returns

• 0 - Success
  

• Negative Value - Failure (Possible Error Codes - 0xfffffffe, 0xfffffffd, 0xfffffffc, 0xfffffffb, 0xffffffe0)
  

Note

• Precondition - rsi_emb_mqtt_connect() API needs to be called before this API.

• Refer to Error Codes for the description of above error codes.

• Length of the topic Length should not exceed 200 bytes excluding NULL termination character.

rsi_emb_mqtt_subscribe#

int32_t rsi_emb_mqtt_subscribe (uint8_t qos, int8_t * topic)

Subscribe to the topic specified. Thus, MQTT client will receive any data that is published on this topic. This is a blocking API.

Returns

• 0 - Success
  

• Negative Value - Failure (Possible Error Codes - 0xfffffffe, 0xfffffffd, 0xfffffffc, 0xfffffffb, 0xffffffe0)
  

Note

• Precondition - rsi_emb_mqtt_connect() API needs to be called before this API.

• Refer to Error Codes for the description of above error codes.

• Length of the topic Length should not exceed 200 bytes excluding NULL termination character.

rsi_emb_mqtt_unsubscribe#

int32_t rsi_emb_mqtt_unsubscribe (int8_t * topic)

Unsubscribe to the topic specified.Thus, MQTT client will not receive any data published on this topic. This is a blocking API.

Returns

• 0 - Success
  

• Negative Value - Failure (Possible Error Codes - 0xfffffffe, 0xfffffffd, 0xfffffffc, 0xfffffffb, 0xffffffe0)
  

Note

• Precondition - rsi_emb_mqtt_connect() API needs to be called before this API.

• Refer to Error Codes for the description of above error codes.

• Length of the topic Length should not exceed 200 bytes excluding NULL termination character.

rsi_emb_mqtt_disconnect#

int32_t rsi_emb_mqtt_disconnect ( Void)

Disconnect the client from MQTT Server/Broker. TCP and MQTT level disconnection take place here. This is a blocking API.

Returns

• 0 - Success
  

• Negative Value - Failure (Possible Error Codes - 0xfffffffd, 0xfffffffc, 0xfffffffb, 0xffffffe0)
  

Note

• Precondition - rsi_emb_mqtt_connect() API needs to be called before this API.

• Refer to Error Codes section for the description of the above error codes Error Codes.

rsi_emb_mqtt_destroy#

int32_t rsi_emb_mqtt_destroy ( Void)

Delete MQTT clients profile configuration. TCP level disconnection happens here, if required. This is a blocking API.

Returns

• 0 - Success
  

• Negative Value - Failure (Possible Error Codes - 0xfffffffd, 0xfffffffc, 0xfffffffb, 0xffffffe0)
  

Note

• Precondition - rsi_emb_mqtt_client_init() API needs to be called before this API, based on requirement.This API can also be issued after rsi_emb_mqtt_disconnect() API.

• Refer to Error Codes for the description of above error codes.

rsi_emb_mqtt_register_call_back#

int32_t rsi_emb_mqtt_register_call_back (uint32_t callback_id, void(*)(uint16_t status, uint8_t *buffer, const uint32_t length) call_back_handler_ptr, status, buffer, length)

Register callbacks for MQTT Asynchronous messages. This is a non-blocking API.

• Need to call rsi_emb_mqtt_connect() API

RSI_WLAN_NWK_EMB_MQTT_PUB_MSG_CB

Called when MQTT client receives the data which was published by other clients on the subscribed topic

• Need to call rsi_emb_mqtt_subscribe() API

RSI_WLAN_NWK_EMB_MQTT_KEEPALIVE_TIMEOUT_CB

Called when keep alive timeout has occurred

• Need to call rsi_emb_mqtt_connect() API

Returns

• Status of the call_back_handler_ptr

Note

• callback_id
  

  ID	Description
  RSI_WLAN_NWK_EMB_MQTT_REMOTE_TERMINATE_CB	If registered, this callback notifies the application of disconnection with the MQTT broker.
  RSI_WLAN_NWK_EMB_MQTT_PUB_MSG_CB	If registered, this callback provides MQTT publish received data to the application.
  RSI_WLAN_NWK_EMB_MQTT_KEEPALIVE_TIMEOUT_CB	If registered, this callback notifies the application of MQTT keepalive response timeout, i.e., ping response is not received within the MQTT Command ACK Timer.

rsi_cal_mqtt_packet_len#

int32_t rsi_cal_mqtt_packet_len (int32_t rem_len)

Calculate length of MQTT packet. This is a non-blocking API.

Returns

• Length of MQTT packet (adjusted rem_len)