Problem With MQTT in AWS using EC200U-CN

Help Needed : “+QMTSTAT: 0,1” Error with EC200 Module and MQTT

I’m currently working on a project that involves using the EC200 module for MQTT communication. I’ve been experiencing an issue with the +QMTSTAT: 0,1 response that I frequently encounter. I’m hoping to get some guidance or insights from the community to help me resolve this issue.

Here’s some background information:

  • I’m using the EC200 module to establish an MQTT connection with AWS IoT.
  • I’m following the steps outlined in the official documentation and various guides to set up SSL certificates, establish the connection, and publish messages.
  • Despite following the steps carefully, I keep receiving the +QMTSTAT: 0,1 response, which indicates an error.

Here’s a snippet of the AT command sequence I use to make a connection with AWS.
Everything works well till Command 14,
Then “+QMTSTAT: 0,1” Error occurs.

1. AT+QMTCFG="recv/mode",0,0,1
2. AT+QMTCFG="SSL",0,1,2
3. AT+QFUPL="UFS:cacert1.pem",1758,100 
4. AT+QFUPL="UFS:client.pem",1250,100
5. AT+QFUPL="UFS:user_key1.pem",1719,100
6. AT+QSSLCFG="cacert",2,"UFS:cacert1.pem"
7. AT+QSSLCFG="clientcert",2,"UFS:client.pem"
8. AT+QSSLCFG="clientkey",2,"UFS:user_key1.pem"
9. AT+QSSLCFG="seclevel",2,2
10. AT+QSSLCFG="sslversion",2,4
11. AT+QSSLCFG="ciphersuite",2,0xFFFF
12. AT+QSSLCFG="ignorelocaltime",2,1
13. AT+QMTOPEN=0,"",8883 
14. AT+QMTCONN=0,"Client-ID"
15. AT+QMTSUB=0,1,"My/topic",1

Here is a Screenshot

If anyone has encountered this +QMTSTAT: 0,1 error before or has experience with EC200 and MQTT, I would greatly appreciate any insights, suggestions, or troubleshooting steps you could provide.

Thank you :slightly_smiling_face: in advance for your time and assistance. Your help will be invaluable in resolving this issue and making progress with my project.

Hi @Meet_Patel
I checked your steps and it seems to be fine. You can use coolwatche to capture the complete connection process. From the phenomenon, it is disconnected immediately after being connected.

Thank you for your input, @lyman-Q .I appreciate your suggestion. However, I’m not familiar with what “coolwatche” is or how to use it. Could you please provide more details about this tool? Is it a specific utility or software that can help monitor and capture device communication? Any additional information you can provide would be greatly appreciated, as I’d like to explore this option to troubleshoot the disconnection issue further.

Can you connect and subscribe using the same credentials without using this modem?
Please do not use screenshots to show text.

@jfrog Yes, I tested connecting and subscribing to the MQTT broker using the same credentials without using the modem.(EC200)

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