Ublox SARA-R4 Series User Manual (English)

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SARA-R4/N4 series-AT Commands Manual

UBX-17003787 - R09

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24MQTT

Page 254 of 307

Type Syntax Response Example

MQTT Message

URC +UUMQTTCM: <op_code>,<num_

unread_msgs> [Topic Len: <topic_

length>] [Topic: <topic_name>]

[Len: <msg_length> Qos: <Qos>]

Message: <message_contents>

+UUMQTTCM: 6,1 Topic: "/sensor/

heat/SD/bldg5/DelMarConfRm"

Len: 16 QoS: 0 Message: "16 bytes of

data"

24.5.3Defined values

Parameter Type Description

<op_code> Number MQTT command request. Allowed values:

• 0: logs out/disconnects from MQTT server. Will message will not be sent

• 1: logs in/connects to MQTT server

• 2: publish a message to a specific topic to the MQTT message broker

• 3: publish a message from a file to a specific topic to the MQTT message broker

• 4: subscribe to a topic from the MQTT message broker

• 5: unsubscribe to a topic from the MQTT message broker. This should exactly

match the Topic Filter used during the Subscribe

• 6: read all unread messages received from MQTT message broker, at the terse/

verbose mode set at the time of message reception

• 7: sets the terse/verbose format for received messages (i.e. the amount of

information and headers with each received MQTT message)

• 8: ping the MQTT message broker

<QoS> Number Quality of service:

• 0 (default value): at most once delivery

• 1: at least once delivery

• 2: exactly once delivery

<retain> Number Allowed values:

• 0 (default value): the message will not be retained at the MQTT server across

disconnects from MQTT client

• 1: the message will be retained by the MQTT server across disconnects from MQTT

client (until superceded by another message)

<hex_mode> Number Allowed values:

• 0 (default value): ASCII input for <message_contents>

• 1: hexidecimal input for <message_contents>

<message_

contents>

String ASCII or hexidecimal data. The starting quotation mark shall not be taken into

account like data. At the end of the byte stream, another quotation mark is provided

for user convenience and visualization purposes.

<mqtt_server> String IP address or URL of MQTT server

<num_unread_

msgs>

Number Indicates the number of unread received messages.

<topic_length> Number Specifies the number of octets in <topic_name>

<topic_name> String Indicates the topic to which the given MQTT message was published

<msg_length> Number Specifies the number of octets in <message_contents>

<reason> Number Result of an MQTT subscribe request:

• 0: success

• 128: failure

<MQTT_result> Number Result of an MQTT command request:

• 0: fail

• 1: success

<login_result> Number Result of an MQTT login request.

• 0: connection accepted

• 1: the server does not support the level of the MQTT protocol requested by the Client

• 2: the client identifier is correct UTF-8 but not allowed by the Server

• 3: the network connection has been made but the MQTT service is unavailable

• 4: the data in the user name or password is malformed

• 5: the client is not authorized to connect

• 6-255: reserved for future use

Other manuals for Ublox SARA-R4 Series

System Integration Manual157 pages

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Ublox SARA-R4 Series Specifications

General

Operating Temperature	-40°C to +85°C
Category	Cellular Module
Technology	LTE Cat M1, LTE Cat NB1
Frequency Bands	B1, B2, B3, B4, B5, B8, B12, B13, B18, B19, B20, B25, B26, B28, B39
Interfaces	UART, USB, I2C, GPIO
Protocols	TCP/IP, UDP, HTTP, HTTPS, MQTT, LWM2M
Security	TLS/SSL, DTLS, Secure Boot
Certifications	GCF, PTCRB, CE, FCC, IC