摘要:
A logical grouping of facilities within a computer development system where said facilities include breakpoint control, trace control and memory, a plurality of VLSI emulators, a plurality of storage device emulators, a plurality of emulators for simulating program or microprogram storage, and may be selectively assigned to said grouping by a user. Said selectively assigned facilities are associated with a clock control and are used for the design, debugging and testing of computer systems.
摘要:
A pair of similar, 32-bit, error detection and correction devices, including a "lower 32-bit" device (210) and an "upper 32-bit" device (212) are configured as a 64-bit, error detection and correction system. When a (64-bit) word of data is being stored in memory, the lower 32-bit device (210) develops, on an inter-device bus (226), signals representing generation partial check bits. The upper 32-bit device (212) receives the partial check bits (226), and develops signals representing final check bits (236) for storage with the corresponding data word in memory (220 and 234). When a (64-bit) word of data is being retrieved from memory, from signals representing check bits retrieved from memory (222), the lower 32-bit device (210) generates on an inter-device bus (224), signals representing correction partial syndromes. From the correction partial syndromes (224), the upper 32-bit device (212) develops, on another inter-device bus (228), signals representing correction partial check bits; generates full syndromes; and corrects errors in the upper 32-bits of the corresponding retrieved data word (240). From the correction partial check bits (228) the lower 32-bit device (210) (also) generates full syndromes; and corrects errors in the corresponding lower 32-bits of the retrieved data word (230).
摘要:
A diagnostic circuit of the present invention has serial command input and output pins separate from its serial data input and output pins. In one embodiment, the diagnostic circuit has one command register and one data register, the data register receiving serially an input signal and providing serially an output signal through an input pin and an output pin respectively. In another embodiment, the diagnostic circuit has one command register and multiple data registers. Each data register including a zero-length register, can be separately addressed. In yet another embodiment, multiple serial data input and output pins are provided together with multiple data registers.
摘要:
The combination of a seven-port random access memory (RAM) unit, a funnel shifter, a mask generator, an arithmetic logic unit (ALU), a merge logic unit, a number of multiplexers, and three bi-directional data buses are configured to form a thirty-two bit, cascadable, microprogrammable, bit-slice suitable for executing complex operations such as those which require that several operands be read from the memory unit, be rotated in the funnel shifter, be operated upon by the arithmetic logic unit, be merged in the merge logic unit, and the result be written back into the memory unit all in a single cycle.
摘要:
A content addressable memory (CAM) system that includes first and second CAM arrays, which generate first and second sets of match control signals, respectively, having higher and lower priorities, respectively. The first CAM array is enabled during a first memory cycle, and the first set of match control signals are analyzed. If a match exists in the first CAM array, a first priority encoder is enabled to process the first set of match control signals. If no match exists, the first priority encoder is not enabled, and a second memory cycle is initiated. The second CAM array is enabled during the second memory cycle, and the second set of signals is analyzed. If a match exists in the second CAM array, a second priority encoder is enabled to process the second set of match control signals. If no match exists, the second priority encoder is not enabled.
摘要:
A memory system includes a memory, an input circuit and a logic circuit. The input circuit is coupled to receive a memory address and, during a write operation, the corresponding write data to be written into the SRAM. The logic circuit causes the write data to be stored in the input circuit for the duration of any sequential read operations immediately following the write operation and then to be read into the memory during subsequent write operation. During the read operation, data which is stored in the write data storage registers prior to being read into the memory can be read out from the memory system should the address of one or more read operations equal the address of the data to be written into the memory while temporarily stored in the write data storage registers. Thus, no “bus turnaround” down time is experienced by the system thereby increasing the bandwidth of the system. The system can operate in a single pipeline mode or a dual pipeline mode.
摘要:
A memory system including a memory array, an input circuit and a logic circuit is presented. The input circuit is coupled to receive a memory address and a set of individual write controls for each byte of data word. During a write operation, the input circuit also receives the corresponding write data to be written into the SRAM. The logic circuit causes the write data and write control information to be stored in the input circuit for the duration of any sequential read operations immediately following the write operation and then to be read into memory during a subsequent write operation. During the read operation, data which is stored in the write data storage registers prior to being read into the memory can be read out from the memory system should the address of one or more read operations equal the address of the data to be written into the memory while temporarily stored in the write data storage registers.
摘要:
A memory system includes a memory, an input circuit and a logic circuit. The input circuit is coupled to receive a memory address and, during a write operation, the corresponding write data to be written into the SRAM. The logic circuit causes the write data to be stored in the input circuit for the duration of any sequential read operations immediately following the write operation and then to be read into the memory during subsequent write operation. During the read operation, data which is stored in the write data storage registers prior to being read into the memory can be read out from the memory system should the address of one or more read operations equal the address of the data to be written into the memory while temporarily stored in the write data storage registers. Thus, no "bus turnaround" down time is experienced by the system thereby increasing the bandwidth of the system. The system can operate in a single pipeline mode or a dual pipeline mode.
摘要:
A memory system includes a memory, an input circuit and a logic circuit. The input circuit is coupled to receive a memory address and, during a write operation, the corresponding write data to be written into the SRAM. The logic circuit causes the write data to be stored in the input circuit for the duration of any sequential read operations immediately following the write operation and then to be read into the memory during subsequent write operation. During the read operation, data which is stored in the write data is storage registers prior to being read into the memory can be read out from the memory system should the address of one or more read operations equal the address of the data to be written into the memory while temporarily stored in the write data storage registers. Thus, no "bus turnaround" down time is experienced by the system thereby increasing the bandwidth of the system. The system can operate in a single pipeline mode or a dual pipeline mode.
摘要:
A multi-error detector uses single byte error correcting-double byte error detecting codes but detects some multiple errors including double, triple, quadruple and more errors in a code. To detect the multiple errors, the multi-error detectors uses error pointer and a syndrome which are generated by error correction circuitry. Multiple errors are indicated when the syndrome indicates an error and either none or more than one of the error pointers are set. In one embodiment, a tree of half adders has least significant output bits from the adders coupled to input terminals of subsequent adders in the tree. Circuit logic detects multiple errors from the least significant output bit of the last adder in the tree and the more significant output bits from all the adders.