Hello guys!
I have an issue sending 0 payload to a topic using the BC92 GSM module. Is it possible to do so?
Module info:
ATI␍␊
Quectel_Ltd␍␊
Quectel_BC92␍␊
Revision: BC92RBR01A05␍␊
AT+CGMI␍␊
Quectel_Ltd␍␊
Quectel_BC92␍␊
Revision: RDA_8909B␍␊
Precoditions
AT+QMTOPEN=1,"mymqtthost",1883␍␍␊
OK␍␊
␍␊
+QMTOPEN: 1,0␍␊
AT+QMTCONN=1,"myuid"␍␍␊
OK␍␊
␍␊
+QMTCONN: 1,0,0␍␊
AT+CMEE?␍␊
+CMEE: 2␍␊
␍␊
OK␍␊
Outputs
AT+QMTPUB=?␍␊
+QMTPUB: (0-5),<msgID>,<qos>,<retain>,"<topic>",(0-1460),"<msg>"␍␊
␍␊
OK␍␊
AT+QMTPUB=1,0,0,1,"topic",0,""␍␊
ERROR␍␊
AT+QMTPUB=1,0,0,1,"topic",0␍␊
> <0x1a>␍␊
ERROR␍␊
AT+QMTPUB=1,0,0,1,"topic"␍␊
> <0x1a>␍␊
ERROR␍␊
Greetings!
I’m still wondering if I’m doing something wrong or if the expected command and documentation aren’t providing some important context. Any ideas?
For reference, I’m looking to implement the equivalent of MQTT client publishing a null (zero length) message as mosquitto_pub -t "topic" -r -n
Greetings!
Sorry, BC92 does not support PUBLISH with 0 length and 0 characters
Thanks for the answer, @herbert.pan-Q !
Could you recommend another module that supports this? Also, can I do some workaround with my BC92 module to include this feature?
Greetings!
Why do you need to test 0 characters and 0 length？
Device bidirectional communication with application server requires the deletion of a retained message as an acknowledgment of the received message from the end device.
Edit: By the protocol of an IoT app that I’m looking to connect my device
Can this function be implemented?
1 Like
