Abstract: A method and apparatus implement redundant memory access using multiple controllers on the same bank of memory, and a design structure on which the subject circuit resides is provided. A first memory controller uses the memory as its primary address space, for storage and fetches. A second redundant controller is also connected to the same memory. System control logic is used to notify the redundant controller of the need to take over the memory interface. The redundant controller initializes if required and takes control of the memory. The memory only needs to be initialized if the system has to be brought down and restarted in the redundant mode. This invention allows the system to continue to stay up and continue running during a memory controller or link failure.

Abstract: An apparatus and method for simulation and testing of electronic systems using a single model that has the composite behavioral information of multiple parts. The single model allows the designer to simulate using one model that captures the anticipated extremes (best case behavior to worst case behavior) across a collection of devices from different vendors.

Abstract: A method, apparatus and computer program product are provided for implementing vertically coupled noise control through a mesh plane in an electronic package design. Electronic package physical design data are received. Instances of vertically coupled noise in the electronic package physical design data are identified. The identified instances of vertically coupled noise are quantified. Then the electronic package physical design data are modified to limit the vertically coupled noise.

Abstract: An apparatus includes a virtual memory manager that moves data from a first block to second block in memory. When the virtual memory manager is ready to transfer data from the first block to the second block, a third, temporary block of memory is defined. The translation table in a DMA controller is changed to point DMA transfers that target the first block to instead target the temporary block. The virtual memory manager then transfers data from the first block to the second block. When the transfer is complete, a check is made to see if the DMA transferred data to the temporary block while the data from the first block was being written to the second block. If so, the data written to the temporary block is written to the second block. A hardware register is preferably used to efficiently detect changes to the temporary block.

Abstract: A heat sink apparatus having a plurality of chips attached to a first surface of a flexible carrier and a plurality of heat sink fins. One or more additional chips may be attached to a second surface of the flexible carrier. The flexible carrier has at least one complementary fold, the complementary fold having a counterclockwise fold and a clockwise fold as seen from the side. A first chip back surface of a first chip and a second chip back surface of a second chip are in thermal contact with a particular heat sink fin, that is, sharing the same heat sink fin. Thermal contact between the chips and heat sink fins is effected by force, by thermally conducting adhesive, by thermal grease, or by a combination of force and/or thermally conducting adhesive and/or thermal grease.

Abstract: A memory controller provides page copy logic that assures data coherency when a DMA operation to a page occurs during the copying of the page by the memory controller. The page copy logic compares the page index of the DMA operation to a copy address pointer that indicates the location currently being copied. If the page index of the DMA operation is less than the copy address pointer, the portion of the page that would be written to by the DMA operation has already been copied, so the DMA operation is performed to the physical address of the new page. If the page index of the DMA operation is greater than the copy address pointer, the portion of the page that would be written to by the DMA operation has not yet been copied, so the DMA operation is performed to the physical address of the old page.

Abstract: A power control method and power control structures are provided for managing a plurality of voltage islands of a functional chip. The power control structure includes a supply control and partition chip positioned between a substrate carrier and a functional chip including a plurality of voltage islands. The supply control and partition chip includes a plurality of first electrical connections to the functional chip including the plurality of voltage islands. The supply control and partition chip includes a plurality of second electrical connections to the substrate carrier. Power applied to predefined ones of the first electrical connections to the functional chip are selectively switched on and off by the supply control and partition chip.

Abstract: Balanced wiring delay within an electronic package is implemented. A plurality of nets in a net group is identified in the electronic package. A predefined structure is added to each net within the group. A balanced wiring delay customizing program systematically processes and reduces length of the nets until a set length balance is obtained for the net group.

Abstract: A power control method and power control structures are provided for managing a plurality of voltage islands of a functional chip. The power control structure includes a supply control and partition chip positioned between a substrate carrier and a functional chip including a plurality of voltage islands. The supply control and partition chip includes a plurality of first electrical connections to the functional chip including the plurality of voltage islands. The supply control and partition chip includes a plurality of second electrical connections to the substrate carrier. Power applied to predefined ones of the first electrical connections to the functional chip are selectively switched on and off by the supply control and partition chip.

Abstract: A memory system having a memory controller and a memory. The memory controller is coupled to a processor and to the memory. The memory comprises one or more daisy chains of memory chips. An address/command word is chained through a daisy chain of memory chips and is handled by one of the memory chips in the daisy chain of memory chips. Data to be written to a memory chip is sent as part of the address/command word, or is transferred on an outgoing data bus chain. Data read from a memory chip is transferred on an incoming data bus chain. A daisy chain of memory chips can include memory chips on multiple carriers, or the daisy chain of memory chips can all be attached to a single carrier.

Abstract: A computer system having a memory system, the memory system having a memory controller and a memory. The memory comprises one or more daisy chains of self timed memory chips. An address/command word is chained through a daisy chain of memory chips and is handled by one of the memory chips in the daisy chain of memory chips. Data to be written to a memory chip is sent as part of the address/command word, or is transferred on an outgoing data bus chain. Data read from a memory chip is transferred on an incoming data bus chain. Access timing on each memory chip is determined by a self time block on each memory chip.

Abstract: A memory chip suitable for use in a daisy chain of memory chips. The memory chip receives an address/command word on a first input, determines if the address command word is directed to the memory chip; if so, the memory chip accesses an array on the memory chip respondent to the address/command word. If not, the memory chip re-drives the address/command word on a first output. Write data is received as part of the address/command word or from a first data bus port. Read data is read from the array or is received from a second data bus port for subsequent re-driving on the first data bus port. A bus clock is received and is used to receive and transmit information on the first input, the first output, the first data bus port and the second data bus port.

Abstract: A method and structure are provided for implementing component placement suspended within electrical pin grid array packages for enhanced electrical performance. A solder column grid array is coupled between a printed circuit board and a first level package. A component is connected between a predefined pair of adjacent columns in the solder column grid array suspended between the printed circuit board and the first level package.

Abstract: A memory chip having a data bus having a plurality of bits. The number of bits is apportioned between a read portion and a write portion. The write portion is dedicated to receiving data that is to be written into an array on the memory chip; the read portion is dedicated to driving data that has been read from the array on the memory chip. The apportionment is programmable. Apportionment can be specified by programming signal pins on the memory chip, connecting the signal pins to appropriate logical values. The apportionment can alternatively be specified by scanning apportionment information into the memory chip at bring up time. The apportionment and also alternatively be specified by receiving apportionment information in an address/command word.

Abstract: A memory chip suitable for use in a daisy chain of memory chips. The memory chip receives an address/command word on a first input, determines if the address command word is directed to the memory chip; if so, the memory chip accesses an array on the memory chip respondent to the address/command word. If not, the memory chip re-drives the address/command word on a first output. Write data is received as part of the address/command word or from a first data bus port. Read data is read from the array or is received from a second data bus port for subsequent re-driving on the first data bus port. A bus clock is received and is used to receive and transmit information on the first input, the first output, the first data bus port and the second data bus port.

Abstract: A computer system having a memory system, the memory system having a memory controller and a memory. The memory comprises one or more daisy chains of self timed memory chips. An address/command word is chained through a daisy chain of memory chips and is handled by one of the memory chips in the daisy chain of memory chips. Data to be written to a memory chip is sent as part of the address/command word, or is transferred on an outgoing data bus chain. Data read from a memory chip is transferred on an incoming data bus chain. Access timing on each memory chip is determined by a self time block on each memory chip.

Abstract: A memory chip suitable for use in a daisy chain of memory chips. Timing of an array on the memory chip is dynamically determined by circuitry on the memory chip that tracks an access timing of the array. The memory chip is configured to receive an address/command word, determine if the address/command word is directed to the memory chip. If so, the array on the memory chip is accessed according to the address command word. If the address/command word is not directed to the memory chip, the memory chip re-drives the address/command word from an output of the memory chip.

Abstract: A memory system having a memory controller and a daisy chain of memory chips. The memory controller is coupled to memory chips in the daisy chain of memory chips by an address/command bus chain. The memory controller is coupled to memory chips in the daisy chain of memory chips by a data bus chain having a number of data bus bits. The data bus chain has a first portion of data bus bits dedicated to transmitting write data from the memory controller to a memory chip. The data bus chain has a second portion of data bus bits dedicated to transmitting read data from a memory chip to the memory controller. Apportionment of data bus bits between the first portion and the second portion is programmable. Programming is done by pin connection, scanning of a value, or by request from a processor coupled to the memory controller.

Abstract: A memory system having a memory controller and a memory. The memory controller is coupled to a processor and to the memory. The memory comprises one or more daisy chains of memory chips. An address/command word is chained through a daisy chain of memory chips and is handled by one of the memory chips in the daisy chain of memory chips. Data to be written to a memory chip is sent as part of the address/command word, or is transferred on an outgoing data bus chain. Data read from a memory chip is transferred on an incoming data bus chain. A daisy chain of memory chips can include memory chips on multiple carriers, or the daisy chain of memory chips can all be attached to a single carrier.

Abstract: A carrier having at least one self timed memory chip in a daisy chain of memory chips. A first carrier has at least a portion of a daisy chain of memory chips attached to the first carrier. An address/command bus input on the first carrier carries an address/command word to a first memory chip in the daisy chain of memory chips. If the first memory chip determines that the address/command word is not directed to the first memory chip, the first memory chip re-drives the address/command word to a second memory chip in the daisy chain of memory chips using a point to point address/command bus link. If there are no more memory chips on the first carrier, the address/command word is re-driven to an address/command bus off-carrier connector. An array on a memory chip has an access time dynamically determined by how fast the array can be accessed.