How to make the hotel TV play fire warning as soon as it is turned on?

Before the cable TV signal is switched to the control center (or the cable TV access equipment room) through the strong switching module of the fire alarm system, all channels are allowed to accept the fire preset signal source. At present, the fire signal source is generally set as an evacuation plan, and the larger places are preset according to the fire zones of each floor, and they correspond to each other when a fire occurs. It can also assist fire emergency broadcast for evacuation guidance. Like the system you need, you can add a set of DVD as the media source, and record and prepare as needed. According to personal understanding, this technology is widely used in building media at present, but it has not been widely used.