Abstract:
A data processor or a data processing system used in compatible modes among which the number of bits of an address specifying a logical address space varies at the time of referring to a branch address table by extension of displacement of a branch instruction. At the time of generating a branch address of a first branch instruction, the data processor or the data processing system optimizes a multiple with which a displacement is multiplied in accordance with the number of bits of an address specifying a logical address space, adds extended address information to the value of a register, and refers to a branch address table with address information obtained by the addition. The referred information is used as a branch address. A multiple with which the displacement is multiplied can be changed in accordance with the mode.
Abstract:
The present invention provides a data processor or a data processing system which can be used in compatible modes among which the number of bits of an address specifying a logical address space varies at the time of referring to a branch address table by extension of displacement of a branch instruction. At the time of generating a branch address of a first branch instruction, the data processor or the data processing system optimizes a multiple with which a displacement is multiplied in accordance with the number of bits of an address specifying a logical address space, adds extended address information to the value of a register, and refers to a branch address table with address information obtained by the addition. The referred information is used as a branch address. To be adapted to a compatible mode using different number of bits of an address specifying a logical address space, it is sufficient to change a multiple with which the displacement is multiplied in accordance with the mode.
Abstract:
A data processing system including a processor LSI and a DRAM divided into banks, for increasing a ratio of using a fast operation mode for omitting transfer of a row address to the DRAM and for minimizing the amount of logics external to the processor LSI. The processor LSI includes row address registers for holding recent row addresses corresponding to the banks. The contents of the row address registers are compared with an accessed address by a comparator to check for each bank whether the fast operation mode is possible. As long as the row address does not change in each bank, the fast operation mode can be used, thus making it possible to speed up operations, for example in block copy processing.
Abstract:
The feature of the present invention consists in: a processor main circuit for executing program instruction strings on a processor chip; a substrate bias switching unit for switching voltages of substrate biases applied to a substrate of the processor main circuit; and an operation mode control unit for controlling, in response to the execution of an instruction to proceed to a stand-by mode in the processor main circuit, the substrate bias switching unit in such a way that the biases are switched over to voltages for the stand-by mode, and for controlling, in response to an interruption of the stand-by release from the outside, the substrate bias switching unit in such a way that the biases are switched over to voltages for a normal mode, and also for releasing, after the bias voltages switched thereto have been stabilized, the stand-by of the processor main circuit to restart the operation.
Abstract:
The present invention provides a data processor or a data processing system which can be used in compatible modes among which the number of bits of an address specifying a logical address space varies at the time of referring to a branch address table by extension of displacement of a branch instruction. At the time of generating a branch address of a first branch instruction, the data processor or the data processing system optimizes a multiple with which a displacement is multiplied in accordance with the number of bits of an address specifying a logical address space, adds extended address information to the value of a register, and refers to a branch address table with address information obtained by the addition. The referred information is used as a branch address. To be adapted to a compatible mode using different number of bits of an address specifying a logical address space, it is sufficient to change a multiple with which the displacement is multiplied in accordance with the mode.
Abstract:
A main storage apparatus is a synchronous dynamic memory having a plurality of memory banks and a mode register for determining an operation mode, a main storage controller is coupled to a processor and the main storage apparatus, and means to realize controlling of parallel access to a plurality of banks of the memory and controlling of setting of an operation mode to the built-in register is arranged in the main storage controller. Accordingly, the use of a conventional processor of high generality and a conventional memory can be ensured.
Abstract:
A data processor in which a speed of an address translating operation is raised is disclosed. A translation lookaside buffer is divided into a buffer for data and a buffer for instruction, address translation information for instruction is also stored into a translation lookaside buffer for data, and when a translation miss occurs in a translation lookaside buffer for instruction, new address translation information is fetched from the translation lookaside buffer for data. A high speed of the address translating operation can be realized as compared with that in case of obtaining address translation information from an external address translation table each time a translation miss occurs in the translation lookaside buffer for instruction.
Abstract:
A multiprocessor system of the present invention has an address bus, a data bus, first and second processors, four access queues, and a shared memory divided into four banks. The four access queues are constituted by first-in first-out memories for buffering a plurality of access-request addresses transmitted through the address bus. Even if continuous access requests are addressed to one bank of the shared memory, a succeeding access request need not wait for a previous access request to be finished. Accordingly, the throughput of the system can be improved greatly.
Abstract:
A processor system including: a processor having a processor core and a controller core; and a plurality of synchronous memory chips, wherein the processor and the plurality of synchronous memory chips are connected via an external bus; wherein the processor core and the controller core are connected via an internal bus; wherein the plurality of synchronous memory chips are operated according to a clock signal; wherein the controller core comprises a mode register selected by an address signal from the processor core and written with an information by a data signal from the processor core to select the operation mode of the plurality of synchronous memory chips, and a control unit to prescribe the operate mode to the plurality of synchronous memory chips based on the information written in the mode register, wherein the controller core outputs a mode setting signal based on the information written in the mode register or an access address signal from the processor core to the plurality of synchronous memory chips via the external bus selectively; and wherein the clock signal is commonly supplied to the plurality of synchronous memory chips.
Abstract:
The feature of the present invention consists in: a processor main circuit for executing program instruction strings on a processor chip; a substrate bias switching unit for switching voltages of substrate biases applied to a substrate of the processor main circuit; and an operation mode control unit for controlling, in response to the execution of an instruction to proceed to a stand-by mode in the processor main circuit, the substrate bias switching unit in such a way that the biases are switched over to voltages for the stand-by mode, and for controlling, in response to an interruption of the stand-by release from the outside, the substrate bias switching unit in such a way that the biases are switched over to voltages for a normal mode, and also for releasing, after the bias voltages switched thereto have been stabilized, the stand-by of the processor main circuit to restart the operation.