The present invention provides the user with the ability to control and administer the supply of memory managed in multiple heaps by a library heap management facility. The control data used by the heap management facility is located in the user-supplied memory. Heaps are created dynamically through calls from the application to the runtime library. Allocation within a heap is performed through calls to the runtime library that canvass the available heap memory for each allocation request. If no...

A method and system for simultaneous retrieval of snoop address information in conjunction with the retrieval/storing of a cache line load/store operation. The method and system are implemented in a data processing system comprising at least one processor having an integrated controller, a cache external to the at least one processor, and an interface between the at least one processor and the external cache. The external cache includes a tag array and a data array. Standard synchronous static R...

A data processing system (20) having a high performance chip select (HPCE) signal, which is functionally programmable to remain asserted for a predetermined number of bus cycles based on an access duty cycle. Bits in an option register (52) allow the user to program HPCE for maintained assertion always, never, or for a number of cycles after a last valid address match. Continued assertion reduces access time to an external device allowing the user to determine the trade-off between high speed ac...

A computer memory system provides a double data rate (DDR) memory output while requiring memory chips with only half the frequency limit of the prior art DDR memory chips. The system contains a first memory bank having data lines and a second memory bank having data lines. The first and second memory banks are associated with first and second clock signals, respectively, where the second clock signal is delayed from the first clock signal such that the data lines of the first memory bank are con...

Disclosed is a method, system, and program for processing data access requests, such as read requests, to a storage location maintained in both a first storage, such as a cache, area and second storage area, such as a disk drive, during a destage operation. A destage operation is granted access to the storage location to destage data from the storage location in the first storage area to the second storage area. During the destage operation, a data access request is granted access to the storage...

With respect to a particular facility semaphore-based synchronizing is executed among a first station and one or more second stations. For each station a single bivalent semaphore is provided. The first station checks all second station semaphores as having a second state relative to its own semaphore's first state. It then executes a first accessing operation and flips the first state. Otherwise it foregoes the first accessing operation. Any second station checks the first station semaphore as ...

In this invention a double data rate (DDR) DRAM is read and written with data coherence. The data is in the form of a data burst either interleaved or sequential and of any length. The data is read from the DDR DRAM depending on whether the starting address is even or odd and taking into consideration CAS latency. Both edges of the clock are used to transfer data in and out of the DDR DRAM. To write data only the starting address of the data burst is used to maintain data coherence. Data coheren...

A method and apparatus for exiting a dynamic random access memory from a low power state is provided. The exit from the low power state is first initiated. After the expiration of an exit delay period, a quiet time command is routed through a queue circuit. In one embodiment the use of a bypass circuit allows the interruption of the memory pipeline with a subsequent restart of the pipeline without excessive delay. A flexible clock is delayed by the onset of the quiet time command until the subse...

The 2 lower bits of a medium sector address that the memory device receives from the host system are used as the data corresponding to a column address in a sector in the flash memory. For instance, with the flash memory having the sector capacity of 2048 bytes and the memory device having the sector capacity of 512 bytes, data transfer control portion when the respective 2 lower bits, 00, 01, 10, and 11 are input, starts the data transfer to the flash memory from the buffer memory at a timing c...

An architecture for an integrated circuit with in-circuit programming, allows for dynamically altering the in-circuit programming instruction set itself; as well as other software stored on the chip. The architecture is based on a microcontroller on an integrated circuit having two or more banks of embedded non-volatile memory arrays which store instructions, including an in-circuit programming instruction set. Using a control program stored on the device, the device interactively establishes an...