stm32+SIM7600CE模块连接阿里云可以连接成功，但是订阅主题时提示订阅无响应

订阅的主题是：/sys/a1XXXXtnOTh/SIM7600CE/thing/service/property/set

命令如下：这指令从说明文档中直接粘贴下来的，相关命令的参数没有修改 AT+CHTPSERV="ADD","www.baidu.com",80,1 OK AT+CHTPUPDATE OK AT+CGDCONT=6, "IP","3gnet" OK AT+CAUTONET=1(重启模块后生效) OK AT+CMAUTH="CwlekguDcv3","device","YpIyrQ 3CKX6WKvNb5bpFKAv254JDhCmu" OK AT+CMPARA="KEEPALIVE",180000 OK AT+CMPARA="TIMEOUT",3000 OK AT+CMPARA="CLEAN",0 OK AT+CMCONN OK AT+CMSUB="get ",1 OK AT+CMYIELD=2000 OK +CMYIELD: 3 到这里发现，返回值是+CMYIELD： 5，表示订阅无响应