摘要:
A secure memory card includes a microprocessor on a single semiconductor chip which interconnects through an internal bus to a number of non-volatile addressable memory chips. The microprocessor includes an addressable non-volatile memory for storing information including a number of key values and program instruction information. Each chip's memory is organized into a number of blocks, each block including a number of rows of byte locations. Each row of each block further includes a lock bit location, the total number of which provide storage for a lock value uniquely coded to utilize a predetermined characteristic of the memory to ensure data protection. Each memory chip is constructed to include security control logic circuits which include a security access control unit and a volatile access control memory containing a plurality of access control storage elements. Under the control of a predetermined set of instructions, the security access control unit performs a predetermined key validation operation by comparing key values against the bit contents of lock bit locations read out a bit at a time during an authentication procedure with a host computer. After the successful performance of the key validation procedure, the microprocessor sets one of the storage elements of the volatile access control memory for enabling user access to block data.
摘要:
A communications controller interface for emulating the previous system employing a plurality of line units in which data is transmitted and received. The interface includes a microprocessor-controlled interface control unit having an interface memory having a plurality of addressable storage locations. The interface memory is mapped by dividing it into a number of groups of locations corresponding to the number of communication lines with each group of locations being subdivided into further locations including a location for storage of receive data, a location for storage of transmit data, and a control location. There are a number of control elements each for generating a sequence of signals for different tasks to be performed by the interface control unit. These control elements are interconnected to the interface control unit and to the interface memory so that the multi-line communications unit is able to access different ones of the control locations for updating the status of the lines and further enabling the microprocessor-controlled interface control unit to transfer data to and from the transmit data and receive data locations of the lines in the predetermined sequence consistent with the status.
摘要:
A high definition page display system for graphics and text utilizing multiple beams in a CRT is disclosed. Information for the several lines which are written simultaneously is made available in parallel. The invention is described in terms of a character set and text generation, but the same principles apply to any other graphic or bit map and to storage in ROMs or loadable RAMs. Each beam of a multiple CRT tube is biased to generate a portion of a character or graphic as it scans across the tube. It takes 12 lines to scan a character with a N-beam tube, 12 over N character scans are therefore required. With the same scanning speed as with a single beam, this factor can be used to increase definition (i.e. number of lines). Also the advantage of multiple beams can be used to reduce scanning speed, if this is useful to improve brightness or spot definition, or to increase the number of dots per line. Reduced scanning speed can also reduce costs, particularly if it brings the scan rate in line with standard components available commerically. Another way to use the advantages would be higher refresh rates.
摘要:
A communications subsystem having a microprocessor coupled to an address bus and a data bus includes a latching register also coupled to the address bus and the data bus. The latching register is responsive to signals from the data bus and address bus for storing bits representative of a direct connect mode, a clear to send mode, and a bit oriented or byte control protocol mode.
摘要:
A data processing system includes a plurality of system units all connected in common to a system bus. The system units include a central processor (CPU), a memory system and a high speed buffer or cache system. The cache system is word oriented and comprises a directory, a data buffer and associated control logic. The CPU requests data words by sending a main memory address of the requested data word to the cache system. If the cache does not have the information, apparatus in the cache requests the information from main memory, and in addition, the apparatus requests additional information from consecutively higher addresses. If main memory is busy, the cache has apparatus to request fewer words.
摘要:
A memory having a plurality of word locations, each having a bit location, includes a parity word in one of the word locations. Bit selector means selects a column of bits made up of like positioned bits in each of the word locations. All bits in a column are added together to indicate whether there is a successful parity check. Each such column is successively checked thereby verifying the integrity of the stored information on a column basis.
摘要:
A firmware state apparatus for controlling data transfer on multiple independent data lines between a telephone communications system and computer system. At least one processor having a program counter is employed for control data transfer. A processor memory is associated with the processor and has a plurality of firmware instructions divided into groups based upon the number of predefined states which are required for performing data transfer. Certain groups of instructions include test instructions for evaluating conditions related to the line to control sequencing to a next one of the predefined states. A shared memory has a plurality of locations for line table information for at least one line with at least one location containing a program counter address specifying a starting instruction of a corresponding one of the group of instructions to be executed by the processor. The processor, in response to the group of instructions, performs a designated operation for the line and in particular in response to the test instruction loads a new value corresponding to the starting instruction of the group of instructions of the next state.
摘要:
A computer system includes a first processor with main memory, an input/output processor with associated memory and an archival memory. Prior to reloading a new operating system from archival memory into the main memory, information such as timer information is stored in the input/output memory. The input/output memory continues to update the timer information until the second operating system is bootstrap loaded into the main memory. The timer and other information may then be returned to the first processor and main memory for use by the second operating system.
摘要:
A Loadable Character Generator whose operation can be changed to suit various needs, such as foreign language requirements, without hardware change and with minimum hardware. The character generator translates the character code of a character to be displayed to the dot pattern for that particular character, utilizing a minimum of hardware. The loadable character generator of the invention replaces the ROM/PROM by a RAM utilizing 2K and 8 RAM memories, a 4K by 8 memory, 4 MUX chips, and a Motorola 6845 CRT Controller with various registers and is loaded through the attribute buffer.
摘要:
A data processing system operating in a bit oriented protocol (BOP) mode of operation senses a transmit underrun; that is, the subsystem is not receiving data from a microprocessor fast enough to maintain the synchronous transmission over the communication line. Apparatus senses the transmit underrun state and generates an abort sequence of bits containing from 8 to 13 successive binary ONE bits.