Abstract:
Digital circuitry performs arithmetic operations upon first and second binary coded decimal digit strings input thereto. The digital circuitry provides for receiving and storing a first and second BCD digit, the digits having an arbitrary data type format. The first and second data types are selected from the group of packed and unpacked data. The circuitry then performs the arithmetic operation upon the stored BCD digits to obtain a result data word which is made available in a data type format corresponding to a selected one of the input BCD digits. In a particular embodiment, a plurality of the circuits can be operated in a digit slice structure. The digit slice structure operates upon strings of packed, unpacked, and mixed data type arithmetic operands and provides, at its output lines, output data in a format corresponding to a selected input data type. In particular, a unique interconnection of the plural output lines of the circuitry enables the output data type to be packed or unpacked as desired. The circuitry also provides for automatic selection of digits applied to the circuitry thereby relieving the operating environment from significant time consuming and costly supervision.
Abstract:
An address translation method and apparatus is disclosed for use in an auxiliary memory of a computer, which stores data in association with a tag defining its location in a main memory, and also includes a buffer for storing a plurality of addresses together with translations of the corresponding main memory locations, permitting data obtained from the auxiliary memory to be validated by comparing the tag with the translation from the buffer. An improvement in the auxiliary memory is disclosed consisting of a content addressable memory (CAM) for storing translations not found in the buffer. The CAM is adapted so that it can be searched for a translation and the translation, if found in the CAM, is employed to verify data in the auxiliary memory.
Abstract:
A support for a CRT monitor provides translational movement for the monitor in two perpendicular directions. The support is on rollers for movement over a horizontal surface, and includes telescoping arms for movement in a first direction. One of the arms enters an elongate guide channel mountable on the surface and includes rollers for rolling along a vertical wall of the channel so that the support moves in a second direction perpendicular to the first. The channel includes a cover and end walls.
Abstract:
A multiprocessor data processing system in which a number of independent processors can concurrently operate on a shared memory even when one processor is performing a read-modify-write (RMW) operation, the system having a locking, content-associative write buffer and a controller for identifying RMW requests, for addressing the buffer and, for issuing directives to lock the buffer, to validate particular data blocks in the buffer and to transfer data back and forth between the processors, the memory and the buffer.
Abstract:
A communications network including a plurality of terminals coupled together to provide a unidirectional communications ring. Each of the terminals is coupled in series along the ring. Each terminal is adapted to transmit (at an associated data rate) a digital signal to the next downstream terminal on the ring. Each terminal is adapted to receive a digital signal at the data rate associated with the next upstream terminal. The received digital signal is applied to a phase locked loop characterized by a hold time which exceeds its lock time. The phase locked loop extracts a local timing signal for re-clocking the received digital signal. The transmission time of N bits is less than the hold time of the phase locked loop. Each terminal monitors the re-clocked signal to identify when same valued consecutive bits are received for a period less than the phase locked loop hold time, and upon such detection to cause that terminal to generate at least one transition.