HOT-LINE INSERTION/EXTRACTION CONTROL UNIT FOR EXTENDED INPUT/OUTPUT DEVICE TO COMPUTER MAIN BODY

摘要

PROBLEM TO BE SOLVED: To decrease the number of signals at the time of connection and to enable hot-line insertion and extraction independent of software by copying initialized data of registers of a 1st I/O controller to registers of a 2nd I/O controller when the extended input/output device is connected to a computer main body. SOLUTION: An I/O controller 13 and a switching controller 14 are initialized by receiving initialization data from a system bus 15 controlled by a system controller 12. When the connector 16 of the computer main body 1 and the connector 24 of the extended input/output device 2 are connected, an active connection detection signal is inputted to the switching controller 14. Consequently, the switching controller 14 detects the connection between the computer main body 1 and extended input/output device 2. The switching controller 14 temporarily obtains the right to control the system bus 15 from the controller 12 and copies all the register information in the I/O controller 13 to the I/O controller 22 of the extended input/output device 2.