911 results about "Address bus" patented technology

A system provides pseudo-concurrency for a volatile memory and a non-volatile memory on a same data bus. In one system embodiment, the volatile memory is coupled to its own address bus, and the non-volatile memory is coupled to its own address bus. In another system embodiment, the volatile memory and non-volatile memory are coupled to a multiplexed address bus. Concurrent with an access cycle to the volatile memory, the non-volatile memory may be precharged. After the access cycle to the volatile memory, a data cycle to a non-volatile memory may be executed. Concurrent with an access cycle to the non-volatile memory, the volatile memory may be precharged. After the access cycle to the non-volatile memory, a data cycle to the volatile memory may be executed.

Methods and apparatus for a memory system using line termination circuits in each memory unit (e.g., integrated circuit memory device) are disclosed. The memory unit contains termination control logic that sets the state of a controllable termination circuit to control reflections on the data bus. The termination control logic determines the proper state for the termination circuit from the state of its memory unit, and in some cases, from the approximate state of the data bus as gleaned from commands decoded from the command/address bus. A termination configuration register on the unit can be used to define the appropriate termination state for each unit state and/or data bus state.

A single chip microcomputer comprises a central processing unit (CPU) 2, a on-chip RAM 3, a on-chip ROM 5, a first bus DBUS for connecting the CPU, RAM, and ROM with one another and transferring data between them, a second bus ABUS for passing address data corresponding to the data passed through the first bus, a third bus SDBUS for connecting the CPU 2 with the RAM 3 and transferring data between them, the number of bits of the third bus SDBUS being larger than that of the first bus DBUS, and a fourth bus BABUS for connecting the CPU 2 with the RAM 3 and passing address data corresponding to the data passed through the third bus SDBUS. The CPU 2 has a data memory RF serving as general purpose registers for providing internal data to the third bus SDBUS, and a bank specifying register BP for holding positional data of a mapping region in the RAM 3 where the contents of the data memory RF are mapped and providing the positional data to the fourth bus BABUS. The RAM 3 has a memory cell array 31, a bank address control circuit 35 connected to the fourth bus BABUS, for generating a real address according to the contents of the bank specifying register BP (BP0, BP1), and a selection circuit 37 for selecting the real address generated by the bank address control circuit 35, or the address provided through the second bus ABUS.

A lockstep processor system adds error detection, isolation, and recovery logic to one or more lockstep processor system functions; namely, control outputs, processor inputs, I/O busses, memory address busses, and memory data busses.

A memory system provides data error detection and correction and address error detection. A Single-byte Error-Correcting/Double-byte Error-Detecting (SbEC/DbED) code with the byte being a 4-bit nibble is used to detect up to 8-bit errors and correct data errors of 4 bits or less. Rather than generating address parity, which is poor at detecting even numbers of errors, a cyclical-redundancy-check (CRC) code generates address check bits. A 32-bit address is compressed to just 4 address check bits using the CRC code. The 4 address check bits are merged (XOR'ed) with two 4-bit nibbles of the data SbEC/DbED code to generate a merged ECC codeword that is stored in memory. An address error causes a 2-nibble mis-match due to the redundant merging of the 4 address check bits with 2 nibbles of data correction code. The CRC code is ideal for detecting even numbers of errors common with multiplexed-address DRAMs.

An improved electrode for neural stimulation, including deep brain stimulation, cortical stimulation, muscle stimulation and other similar applications. The improvement of our invention over prior art consisting of the possibility of a larger number of electrode pads from where to originate the electrical stimulation, thereby offering the possibility of fine control of the location of the stimulating signal. Our invention discloses a system of address wires which controls switches and demultiplexers to select one of a plurality of wires and one of a plurality of electrode pads from where the electric stimulation starts, and latches that maintain some selected choices after the address buses go on to select other wires and other electrode tips. Our invention also discloses time delay lines which are used to keep the stimulating pulses for a pre-assigned time, after which the stimulating pulses stop until further instruction to start again.

A circuit connectable to a microcontroller having an address bus, a data bus, a read line and a write line include a programmable logic device (PLD) array, at least one input pin, at least two databus macrocells and a bit mask register. The input pin is connected to the PLD array and is connectable to the address bus. The databus macrocell is connected to the PLD array and to an external unit and is also connectable to the data bus, the read line and the write line. The bit mask register has at least two bits, each associated with one of the at least two macrocells. The databus can directly access the databus macrocell only if its associated bit in the bit mask register is of the correct state. In another embodiment, the write line carries an edge write signal and the databus accesses the databus macrocell on one edge of the edge write signal.

Apparatuses and methods for selective row refreshes are disclosed herein. An example apparatus may include a refresh control circuit. The refresh control circuit may be configured to receive a target address associated with a target plurality of memory cells from an address bus. The refresh control circuit may further be configured to provide a proximate address to the address bus responsive, at least in part, to determining that a number of refresh operations have occurred. In some examples, a plurality of memory cells associated with the proximate address may be a plurality of memory cells adjacent the target plurality of memory cells.

A control module (100) includes a first signal processing unit (102) that is coupled to a second signal processing unit (114) by a control bus (130), an address bus (131) and a data bus (132). The control module conveys seed value addresses (108) and expected result addresses (110) over the address bus, seed values (118) and verification set output values (107) over the data bus, and compares each verification set output value to an expected result (120), thereby allowing the control module to determine whether the first signal processing unit, the control bus, the address bus, and the data bus are collectively functioning correctly. By properly selecting the seed value addresses, expected result addresses, seed values, and expected results (and correspondingly, verification set output values), proper operation of each line of the address bus and control bus may be individually verified.

A system for repairing embedded memories on an integrated circuit is disclosed. The system comprises an external Built-In Self-repair Register (BISR) associated with every reparable memory on the circuit. Each BISR is configured to accept a serial input from a daisy chain connection and to generate a serial output to a daisy chain connection, so that a plurality of BISRs are connected in a daisy chain with a fuse box controller. The fuse box controller has no information as to the number, configuration or size of the embedded memories, but determines, upon power up, the length of the daisy chain. With this information, the fuse box controller may perform a corresponding number of serial shift operations to move repair data to and from the BISRs and into and out of a fuse box associated with the controller. Memories having a parallel repair interface are supported by a parallel address bus and enable control signal on the BISR, while those having a serial repair interface are supported by a parallel daisy chain path that may be selectively cycled to shift the contents of the BISR to an internal serial register in the memory. Preferably, each of the BISRs has an associated repair analysis facility having a parallel address bus and enable control signal by which fuse data may be dumped in parallel into the BISR and from there, either uploaded to the fuse box through the controller or downloaded into the memory to effect repairs. Advantageously, pre-designed circuit blocks may provide daisy chain inputs and access ports to effect the inventive system therealong or to permit the circuit block to be bypassed for testing purposes.

A wireless communications architecture having first and second synchronous memory devices coupled to a virtual channel memory controller by corresponding first and second data buses, and a shared address and control bus interconnecting the virtual channel memory controller and the first and second synchronous memory devices. The first and second synchronous memory devices are addressed with the shared address bus, and the first and second memory locations are accessed via the first and second data buses, respectively.

A distributed system structure for a large-way, symmetric multiprocessor system using a bus-based cache-coherence protocol is provided. The distributed system structure contains an address switch, multiple memory subsystems, and multiple master devices, either processors, I/O agents, or coherent memory adapters, organized into a set of nodes supported by a node controller. The node controller receives transactions from a master device, communicates with a master device as another master device or as a slave device, and queues transactions received from a master device. Since the achievement of coherency is distributed in time and space, the node controller helps to maintain cache coherency. In order to reduce the delays in giving address bus grants, a bus arbiter for a bus connected to a processor and a particular port of the node controller parks the address bus towards the processor. A history of address bus grants is kept to determine whether any of the previous address bus grants could be used to satisfy an address bus request associated with a data bus request. If one of them qualifies, the data bus grant is given immediately, speeding up the data bus grant process by anywhere from one to many cycles depending on the requests for the address bus from the higher priority node controller.

A memory interface system and method are provided for transferring data between a memory controller and an array of storage elements. The storage elements are preferably SRAM elements, and the memory interface is preferably one having separate address bus paths and separate data bus paths. One address bus path is reserved for receiving read addresses and the other address bus path is reserved for receiving write addresses. One of the data bus paths is reserved for receiving read data from the array, and the other data bus path is reserved for receiving data written to the array. While bifurcating the address and data bus paths within the interface is transparent to the memory controller, the separate paths afford addressing phases of a read and write address operation to be partially overlapped, as well as the data transfer phases. This will essentially reduce the cycle time between a read and write memory access, and proves useful when maximizing the data throughput across the data bus when implementing double data rate (QDR) mechanisms.

Circuits and methods are provided that alleviate overloading of the command address bus and limit decreases in command address bus bandwidth to allow increased numbers of memory modules to be included in a computer system. A plurality of switches is coupled between the command address bus (which is coupled to the memory controller) and a respective plurality of memory modules. Each switch provides command address bus data only to its respective memory module. Preferably, only one switch does so at a time, limiting the loading seen by the memory controller.

A multi-master computer system having overlapped read and write signal with scalable address pipelining programmable increases the depth of address pipelining independently on two overlapped read and write data busses up to "N" deep requests. The system includes a local bus having an address bus, a read bus, and a write bus. Master devices are coupled to separate address, read data and write data buses. Slave devices are attached to the data busses through shared, but decoupled address, read and write data buses. An arbiter is coupled to the data bus and allows masters to compete for bus ownership. The arbiter includes read and write pipeline logic for processing and priortizing master and slave read and write data transfers across the data bus. Programming apparatus alters the read and write pipeline logic for address pipelining

An embedded system is provided with the capability to be debugged. The embedded system includes a central processing unit (CPU) that is coupled to a bus having certain contents. A register, also with contents, is available for loading by the CPU. Finally, a debug logic circuit is also included. The debug logic circuit is coupled to both the bus and the CPU. The debug circuit itself is composed of a breakpoint detect circuit that is coupled to the bus and to the register. This circuitry enables a breakpoint signal that is produced by the breakpoint detect circuit when the contents of the register equal the contents of the bus. A method is also provided for debugging an embedded system having a microcontroller with a CPU. First, a debug logic circuit that resides on the same chip as the microcontroller is programmed to detect a predetermined condition in the microcontroller. Next, application software is run on the microcontroller. When a predetermined condition is detected, the CPU is interrupted which provides the ability to view the condition of the microcontroller. Programming the debug logic circuit can include the storing of a breakpoint address in a breakpoint address register. Afterward, a program memory address bus is selected for comparison to the contents of the breakpoint address register, upon which time a breakpoint counter is set to zero. The steps of interrupting and detecting are accomplished by comparing the contents of the program memory address bus to the contents of the breakpoint register and, if they are equal, then the CPU is interrupted.

The present invention discloses an interactive IR electronic white board, around which is an infrared emitting and receiving array. An output port of a column driver of emitting array is connected to high frequency modulating signal generator, and an output port of a column driver of the receiving array is connected to a microprocessor through a signal receiving circuit and an analog-digital converter A/D. The emitting array and the receiving array are connected to emitting and the receiving driver through emitting and receiving driver lines, and the emitting driver and the receiving driver are connected with the microprocessor through address bus. The present invention utilizes the Inverse Square Law of optical theory and the linear direct ratio relation between the quantity change of light particles received by an infrared receiving diode and the output voltage of the receiving diode to associate the output voltage of the receiving diode with the interrupted width of the infrared light path, so that it can calculate the coordinate of interrupter accurately and improve the resolution of infrared scanning. The present invention can not only distribute pens or erase, but can be used by plurality of users at the same time as well.

Apparatuses and methods for dual channel memory architecture with reduced interface pin requirements are presented. One memory architecture includes a memory controller, a first memory device coupled to the memory controller by a shared address bus and a first clock signal, and a second memory device coupled to the memory controller by the shared address bus and a second clock signal, where the polarity of the second clock signal is opposite of the first clock signal. A method for performing data transactions is presented. The method includes providing addressing signals over a shared address bus to a first memory device and a second memory device, providing clock signals to the memory devices which are reversed in polarity, where the clock signals are derived from a common clock signal, and transferring data to the memory devices over separate narrow data buses in an alternating manner based upon the clock signals.