ADDRESS CONVERTER

PURPOSE:To carry out the address conversion at a high speed by improving a hit ratio by a random replacing algorithm system address converting buffer (TLB). CONSTITUTION:A TLB registering content holding register 4 to store temporarily the content to be renewed and registered as the entry of a TLB 1, and a TLB replacing entry holding register 5 to store temporarily the content before the renewing of the entry of the TLB 1 are provided apart from the TLB 1, and the content stored in the TLB registering content holding register 4 and the TLB replacing entry holding register 5 is handled in the same way as the entry of the TLB 1 and the address conversion is performed. By a TLB hitting signal 11 or register hitting signals 12-1 and 12-2, a physical address 9-7 corresponding to a logical address 8-1 through tristate buffers 7-1, 7-2 and 7-3 is outputted.