Abstract: A computer memory system connectable to a processor and having programmable operational characteristics based on characteristics of the processor. The memory system includes several caches and a main memory connected to a bus. One cache can be programmed to store only code data. Another cache can be programmed to buffer data writes to the main memory only from the processor. The main memory supports fast page mode and can be programmed to selectively reopen either code or non-code data pages.

Abstract: A method and system for managing data elements in a memory system. The memory system is accessible by a plurality of bus masters connected by a bus to the system. Code data elements to be read are predicted. The predicted code data elements are then transferred within the memory system from a slow to high speed memory without delaying memory access requests for data from the bus masters.

Abstract: The invention is a system and method for accessing a plurality of memory banks. The system includes a number of memory banks, a register and a controller. The register stores capacity information of each memory bank. The controller is connected to the register and memory banks and uses the capacity information to determine whether or not addresses are to be interleaved between a pair of memory banks. If the memory banks are of similar capacities, the addresses may be interleaved therebetween.

Abstract: A method for accessing data in a computer memory divided into pages. A first page is opened in response to a first address to access data therein. A second page is opened in response to a second address to access data therein. The first page is then reopened prior to receiving another address signal.

Abstract: A method and system for transferring data elements from a computer main memory to a cache memory. The main and cache memories are accessible by a host processor and other bus masters connected thereto by a bus. Code data elements to be read by the host processor are predicted. The predicted code data elements are then transferred from the main memory to cache memory without delaying memory access requests for data from the other bus masters.

Abstract: A method for reading a multiple byte data element stored in both first and second memories. Selected bytes of the data element are invalidated in the first memory. Valid bytes from the first memory are combined with remaining bytes from the second memory in response to a read request.

Abstract: A circuit, including a state machine, e. g. a logic array and a set of controlled storage devices, receives conditioning signals, such as reset, power failure signals and signals fed back from the storage devices, and uses the signals to determine which of a number of clock sources is to be used in a system. The state machine provides output signals which are processed by a delay circuit to ensure that switches between clock sources only occur during an inactive period of the clock signals to prevent signal glitches. The circuit's output signal controls a number of AND gates, each of which gates a particular clock signal to an output line. When a power fail condition occurs, a switch between a first clock signal and a substantially lower frequency clock signal is required to conserve power.