说明：  电梯门禁系统：包括系统原理图，通信流程图和C语言源程序 AT89C52控制H6152读卡器读写Mifare射频卡并通过CAN总线连接系统主机，CAN总线控制器为SJA1000，收发器为P82C250.
(Door guard system of the lift, Including systematic principle picture and source program . AT89C52 control H6152 card reader to write Mifare radio frequency nip and connect the systematic host computer through CAN bus to read, CAN bus controller is SJA1000, the transceiver is P82C250. )