The core chip of RFID RF electronic lock adopts tx125 series contactless IC control chip of Tongxin intelligent technology. The RF card reading of the chip adopts 125kHz RF, and the card reading distance is 50 ~ 150mm. It fully supports the operation of EM, temic, TK and their compatible cards. In the RFID electronic lock circuit, the baud rate is 9600 when mode1 is connected to the high level, the serial port output is selected when Mode3 is connected to the high level, and the active mode is selected when Mode4 is connected to the high level. The “TXD” of tx125 is connected with P3.7 of MSP430. The working mode of P3.7 is set to the receiving state of serial port 1, and the receiving interrupt of serial port 1 is turned on to maximize the real-time performance of RFID card reading; TX1 and TX2 are connected to the induction antenna, and “status” is connected to the common IO port P1.2 of MSP430 to read the working state of tx125; The common IO port p1.3 of MSP430 is set to the output state, and the action motor of the electronic lock is controlled through the relay to complete the work of opening and locking the door. Other pins of tx125 default to no-load.
RFID electronic lock circuit is shown in Figure 2: