... alarm system adopts SMS data transmission and voice platform of GSM network to send control command and receive alarm remotely, and ... show the time, date and the status of arm, disarm, GSM signal, power, alarm, etc. The specific functions are as follows1 ... software centre15. Check host's status by SMS Specificationsa) GSM frequency:900/1800/850/1900MHz (Optional) b) Alarm mode:SMS data transmission ...