Complete high-performance cache system for the 80386

The 80386 is a high-performance third-generation microprocessor that is now standard in most top-of-the-range PCs. Like all similar processors operating at clock rates above 30 MHz, the 80386 must use cache memory if it is to operate efficiently. Without cache memory, the user must either pay a very high price for very fast RAM or employ slower memory by introducing wait states. This application note describes the 80386 bus interface and demonstrates how it can be interfaced to IDT cache tag RAMs to create a cache system. Although the report describes a relatively basic cache system, it covers all design considerations ranging from system timing to the programming of the PALs needed to implement the interface. A.C.