The system of smart code locks consists of a smart monitor and an electronic lock. The two are placed off-site, and the smart monitor supplies the power required by the electronic lock and receives the alarm and status information it sends. Here, the line multiplexing technology is adopted to share a two-core cable for power supply and information transmission, which improves the reliability and safety of the system.
The basic principle and composition block diagram of the intelligent monitor
The block diagram of the intelligent monitor is composed of a single chip, a clock, a keyboard, an LCD display, a memory, a demodulator, a line multiplexing and monitoring, an A/D conversion, a buzzer and the like. Mainly complete the communication with the electronic lock, intelligent analysis and security monitoring of communication lines.
The intelligent monitor is always in the receiving state and receives the alarm information and status information from the electronic lock in a fixed format. For the alarm information, the sound and light alarms are immediately sent through the LCD display and the buzzer; for the status information, it is stored in the memory and compared with the historical state of the electronic lock before this time, and the trend is changed to predict the future. The status changes, and the corresponding information is provided to the duty officer through the LCD display for decision making. While the intelligent monitor establishes communication with the electronic lock, the A/D converter monitors the change of the supply current flowing through the communication line in real time, effectively preventing the damage caused by human factors and ensuring the smooth communication line.
The basic principle and composition block diagram of electronic locks
The block diagram of the electronic lock, which is also based on the 51 series single chip microcomputer (AT89051), with the corresponding hardware circuit, completes the setting, storage, identification and display of the password, drives the electromagnetic actuator and detects the driving current value, and receives the sensor. The function of alarm signal and data transmission.
The MCU receives the entered code and compares it with the password stored in the EEPROM. If the password is correct, the electromagnetic actuator is unlocked; if the password is incorrect, the operator is allowed to re-enter the password, up to three times; if three times If it is not correct, the MCU will alarm the intelligent monitor through the communication line. The single-chip microcomputer sends the unlocking operation and the driving current value of the electromagnetic actuator as the status information to the intelligent monitor at this time, and also sends the alarm information received from the sensor interface to the intelligent monitor as the basis of the intelligent analysis.