BURST MULTIPLEXER CHANNEL

摘要

PURPOSE:To avoid such a case where one system occupies the same magnetic disk controller for a long time by releasing the use of said controller for other systems when the continuous input/output frequency of the controller reaches a prescribed level after reservation. CONSTITUTION:A counter 54 set to a RAM 42a in a burst multiplexer channel BMC 33a counts the continuous producing frequencies of seek commands of a microprocessor 41a after a magnetic disk controller 20 is reserved by an A system 30a. While the upper limit level of said command producing frequencies is shown by a prescribed value K and set previously at a prescribed value setting part 55 of the RAM 42a. Then the microprocessor 41a decides whether or not the count value of the counter 54 is larger than the value K and then issues a release command to the controller 20 if the count value of the counter 54 reaches the value K. Thus the controller 20 is released for other systems.