MQTT---SUBSCRIBE和SUBACK订阅主题
订阅主题主题/sys/a1fSNCGR0G5/XP001/thing/service/property/set转化为十六进制2F 73 79 73 2F 61 31 66 53 4E 43 47 52 30 47 35 2F 58 50 30 30 31 2F 74 68 69 6E 67 2F 73 65 72 76 69 63 65 2F 70 72 6F 70 65 72 74 7...
