Abstract: Apparatus comprises a processor configured for operation under a sequence of instructions from an instruction set, wherein said processor comprises: means for conditionally inhibiting at least one type of trap, interrupt or exception (TIE) event, wherein, when operating under a sequence of instructions, said inhibition means is inaccessible by said instructions to inhibit the or each type of TIE event, without interrupting said sequence. A data processing apparatus includes a processor adapted to operate under control of program code comprising instructions selected from an instruction set, the apparatus comprising: a predefined memory space providing a predefined addressable memory for storing program code and data, a larger memory space providing a larger addressable memory, means for accessing program code and data within the predefined memory space, and means for controlling the access means so as to enable the access means to access program code located within the larger memory space.

Abstract: Embodiments of the invention relate to a data processing apparatus including a processor adapted to operate under control of an executable comprising instructions, and in any of a plurality of operating modes including a non-privileged mode and a privileged mode, the apparatus comprising: means for storing a plurality of stacks; a first stack pointer register for storing a pointer to an address in a first of said stacks; a second stack pointer register for storing a pointer to an address in a second of said stacks, wherein said processing apparatus is adapted to use said second stack pointer when said processor is operating in either the non-privileged mode or the privileged mode; and means for transferring operation of said processor from the non-privileged mode to the privileged mode in response to at least one of said instructions. Embodiments of the invention also relate to a method of operating a data processing apparatus.

Abstract: A data processing apparatus comprises a processor constructed to operate under control of a sequence of program instructions selected from a predetermined instruction set; master circuitry to request access to storage locations of the processor; an interface circuit to provide an interface for an external apparatus to signal a request for access to the storage locations and an interface for the master circuitry to signal a request for access to the storage locations; and control to provide access between the storage locations and the interface circuit in response to the request only at predetermined points in execution of the stored program, the control being operable to fix periods of time for providing such access relative to the sequence of program instructions such that execution timing of the stored instructions is independent of whether a request is supplied to the interface.

Abstract: A method of filtering radar return signals to discriminate between targets of interest and clutter is presented in which a filter filters radar return signals received by a first radar receiver, based on radar return signals received at another radar receiver, to produce filtered radar return data in which radar return signals received by the first radar receiver for targets of interest are present and radar return signals received by the first radar receiver but arising from clutter are suppressed.

Abstract: A method of classifying items from reflected signals returned from said items is disclosed, the method comprising: processing said return signals to discriminate between a first set of signals indicative of items of interest and a further set of signals indicative of clutter; identifying items from said first set of signals and classifying them as a first class of item; processing said further set of signals to identify a second set of signals indicative of further items of interest; identifying items from said second set of signals and classifying them as a second class of item.

Abstract: Embodiments of the invention relate to a data processing apparatus including a processor adapted to operate under control of an executable comprising instructions, and in any of a plurality of operating modes including a non-privileged mode and a privileged mode, the apparatus comprising: means for storing a plurality of stacks; a first stack pointer register for storing a pointer to an address in a first of said stacks; a second stack pointer register for storing a pointer to an address in a second of said stacks, wherein said processing apparatus is adapted to use said second stack pointer when said processor is operating in either the non-privileged mode or the privileged mode; and means for transferring operation of said processor from the non-privileged mode to the privileged mode in response to at least one of said instructions. Embodiments of the invention also relate to a method of operating a data processing apparatus.

Abstract: An integrated circuit contains a microprocessor core, program memory and separate data storage, together with analog and digital signal processing circuitry. The ALU is 16 bits wide, but a 32-bit shift unit is provided, using a pair of 16-bit registers. The processor has a fixed length instruction format, with an instruction set including multiply and divide operations which use the shift unit over several cycles. No interrupts are provided. external pins of the integrated circuit allow for single stepping and other debug operations, and a serial interface (SIF) which allows external communication of test dat or working data as necessary. The serial interface has four wires (SERIN, SEROUT, SERCLK, SERLOADB), allowing handshaking with a master apparatus, and allowing direct access to the memory space of the processor core, without specific program control.

Abstract: A miniature mounting device on which elements such as optical filters can be accurately held. The device includes a substrate having a machined groove with an enlarged opening for receiving the element, and an overlayer extends at least partially over the groove to clamp the element.

Abstract: An ink jet array printer in which the printing voltage waveform applied to each raster of drops formed in each printing gun comprises at least two successive sets of voltage levels which each arrange the raster drops in a group in time order of drop formation for each set of voltage levels so that corresponding drops in each of the groups formed in the raster, if charged for printing, have similar differences of voltage level and have similarly spaced print locations in the line section of drops printed by the printing gun. First and second correction voltages are applied to the charging voltage levels, the first to correct for the influence of the preceding drop and the second for the electrostatic and aerodynamic drag forces of a small number of drops influencing the drop being corrected. The set of second correction voltages derived for any particular drop being used also for corresponding drops in the other group(s).

Abstract: An apparatus for metering and transporting particulate material, particularly seeds, in which suction is continuously applied to holes in a surface of a drum to enable the particles to be picked up by the drum, an air pressure device being provided to produce an air stream for entraining and accelerating the particles along a transport passage away from the drum surface.