Abstract: A storage drive includes a first memory that stores first text. A first processor generates a first instruction to decrypt the first text. A cryptographic module includes a second memory, a cryptographic device, a memory module, and a second processor. The second memory is inaccessible to the first processor and stores a cryptographic key. The cryptographic device accesses the second memory to obtain the cryptographic key and based on the first instruction, decrypts the first text. The memory module stores a status of execution of the first instruction by the cryptographic device. The second processor, prior to the cryptographic device decrypting the first text, forwards the first instruction to the cryptographic device and stores the status of execution of the first instruction in the memory module. The memory module is connected between the first and second processors and isolates the first processor from the second processor.

Abstract: Cryptographic apparatus having corresponding methods and computer-readable media comprise: a mailbox memory module to store cryptographic commands received from a client over a client bus, wherein the client is external to the cryptographic apparatus; and a secure processor to obtain the cryptographic commands from the mailbox memory module over a first secure internal bus, execute the cryptographic commands, and store a status of execution of the cryptographic commands in the mailbox memory module over the first secure internal bus, wherein the client obtains the status of the cryptographic commands from the mailbox memory module over the client bus.

Abstract: A device includes a data path configured to transfer data from a read channel device to a host. A read gate delay module is configured to receive a first read gate signal, to output a second read gate signal to the read channel device based on the first read gate signal, and selectively delay a transition of the second read gate signal between an asserted state and a non-asserted state based on a data sector size of a data segment and positive and negative edges of a write clock.

Abstract: A disk controller that controls data transfer between a storage device and a host system is provided. The disk controller includes logic having a state machine that controls de-assertion of a read gate signal based on sector size and/or whether a data segment is split or non-split. The read gate signal is de-asserted at programmable times, based on data sector size. The state machine interfaces with a register whose settings indicate to the state machine that next time when the state machine starts executing from an idle state it should process a second half of a split sector. The state machine also uses a register that to extend assertion of the read gate signal. It is noteworthy that the read gate signal is controlled on a positive and negative edge of a write clock signal.

Abstract: The logic circuitry of an IC chip is connected to JTAG register chains which hold state information on each portion of the logic circuitry therein. A JTAG Tracker Module is connected to the controls of each of the JTAG register chains enabling a programmer-operator to read the present state of each JTAG register chain and enabling a readout of the logic circuits condition in a single clock period.

Abstract: A single chip data path gate array interface links a central processing unit, operating at a first clock rate and single word protocol, to dual system busses operating at a second clock rate and multiple-word protocol. The data path interface holds command, data and message registers, controlled by external logic, in an input channel pathway and an output channel pathway. The interface chip is basically limited to registers and multiplexers making it flexible for use in different architectures such as both Store-Through and Non-Store-Through cache protocols. In addition, such a simplified chip is simple to fabricate and to maintain free of defects.

Abstract: A dual bus interface module, providing communication between a processor means and/or translation logic means and a set of dual system busses, provides a programmable transmit logic means which enables bus access for data transfer of commands and message transfer requests to destination modules on said system busses in a manner so as to use any available system bus to complete data transfer requests or to report the status of non-completed requests.

Abstract: An error logging system where errors are captured on dual system busses operating at a lower clock rate (16 MHz) than the processor which receives the error information. The system functions to substantially reduce the loads on the processor in addition to maximizing the use of the system bus drivers which are pin-constrained. The processor operates at a higher clock rate (32 MHz). Processor commands to read error data from an error log register are synchronized down to the 16 MHz rate, then enabled onto a processor bus after a second synchronization operation back to the higher (32 MHz) rate. Provision is made for identifying several different types of error categories.

Abstract: A programmable timing logic system for enabling access to a first or second bus, of dual system busses, by a central processor and/or a protocol-timing translation logic unit wherein messages may be received from one bus while command/control data is being transmitted to the other bus. Incomplete command cycles are retried a specific number "n" of times, each for a preset predetermined time period of "p" microseconds.

Abstract: A message transfer system between digital modules where two or more digital modules operate on separate and different message lengths and clock frequencies and where, temporary storage buffer (translator unit) holds messages being transferred between the different digital modules and acts as a speed matching and word length matching buffer unit to permit compatible transfer of message words. Also, the transfer system recognizes when requests are outstanding from both digital modules and can discard a message from a requesting module. Each of the two or more separate digital modules is serviced by dual system busses providing for redundancy of data transfer operations.

Abstract: A system for controlling and routing messages and data received from dual system busses, through a bus interface unit, to a protocol translation logic means and to a processor in a central processing module connected onto a dual system bus network. The processor operates at a first clock rate and on a single-word communication protocol while the translation logic means operates at a second rate and multiple-word communication protocol. The processor and translation logic are destination modules which receive the benefit of the receiving control logic system. The receiving control logic system also services external modules on the system bus in order to receive data and control the routing of data to the destination modules. Destination modules which are busy and not ready will cause the system to inform the external transmitting modules that they must retry their transmission.

Abstract: A bus interface transfer system enables communication to/from dual busses to multiple resource units which include a central processor module and a translation logic unit which permits data transfer between systems having different protocols and different clock rates.