| 摘要 |
PURPOSE:To reduce the kinds of IC to one kind, by constituting a bus interface circuit by use of the number of blocks for bit-slicing it to the same function unit consiting of a latching circuit, a bus controlling circuit and a selecting circuit. CONSTITUTION:A (write) circuit control part instructs write to a circuit 7 through a control line 8, divides a write address into two and loads it one a common bus. It is latched by a latching circuit and is loaded on an address bus 5. Subsequently, a write data is divided into two, is loaded on a bus 4 and is loaded on a data bus 6 through the latching circuit. A memory write line 12 is selected by a selector, and a main memory is subjected to access. In this way, a bus interface circuit is divided into plural function units having the same circuit configuration, and can be converted to an IC by a function unit, and it can be obtained at a low cost by using plural ICs of only one kind of the bus interface circuit. |
