Apple Inc.

Other

James D Ramsay

Manu Gulati

Erik P Machnicki

Kevin R Walker

Inder M Sodhi

Sanjay Mansingh

Jianlin Yu

Mitchell Palmer Lichtenberg, Jr

An interrupt mechanism is disclosed. In one embodiment an integrated circuit (IC) is coupled to a number of peripheral devices, via a bus, and includes an interface controller. The interface controller includes a bus engine circuit coupled to receive data from the various ones of the peripheral devices, wherein the data may include various requests. The bus engine circuit also includes decoding circuitry configured to decode the data to determine the nature of the requests. Responsive to determining that interrupt information is stored in one or more of the requests, the interrupt information may be written to one of a number of interrupt registers. An interrupt controller may read the interrupt registers to determine the presence of interrupts, and thus initiate the process to see that they are serviced.

Method and apparatus for indicating interrupts

An integrated circuit (IC) having a bridge for interfacing a debugger and method of operating the same is provided. In one embodiment, an IC includes a debug control circuit and a debug interface block (DIB) implemented thereon. The DIB is coupled to the debug control circuit. The IC also includes an interface for a debugger and a number of interfaces for external circuits, each of the interfaces being coupled to the debug control circuit. The debug control circuit may function as a bridge for coupling an external debugger to the DIB and to external circuits coupled to the IC through corresponding ones of the interfaces. The debug control circuit may establish a connection between the debugger and one of the external circuits. Communications between the debugger and the external circuit may be conducted while bypassing the DIB.

Serial wire debug bridge

A system and method for efficiently monitoring traces of multiple components in an embedded system. A system-on-a-chip (SOC) includes a trace unit for collecting and storing trace history, bus event statistics, or both. The SOC may transfer cache coherent messages across multiple buses between a shared memory and a cache coherent controller. The trace unit includes multiple bus event filters. Programmable configuration registers are used to assign the bus event filters to selected buses for monitoring associated bus traffic and determining whether qualified bus events occur. If so, the bus event filters increment an associated count for each of the qualified bus events. The values used for determining qualified bus events may be set by programmable configuration registers.

Programmable resources to track multiple buses

A system and method for efficiently storing traces of multiple components in an embedded system. A system-on-a-chip (SOC) includes a trace unit for collecting and storing trace history, bus event statistics, or both. The SOC may transfer cache coherent messages across multiple buses between a shared memory and a cache coherent controller. The trace unit includes a trace buffer with multiple physical partitions assigned to subsets of the multiple buses. The number of partitions is less than the number of multiple buses. One or more trace instructions may cause a trace history, trace bus event statistics, local time stamps and a global time-base value to be stored in a physical partition within the trace buffer.

Efficient trace capture buffer management

In one embodiment, an SOC includes multiple components including a CPU complex and one or more non-CPU components such as peripheral interface controllers, memory controllers, media components, etc. The SOC also includes an SOC debug control unit, which is coupled to receive detected debug events from the components. Each component may include a local debug control unit that is configured to monitor for various debug events within that component. The debug events may be specific to the component. The local debug control units may transmit detected events to the SOC debug control unit. The SOC debug control unit may detect one or more events from one or more components, and may halt the components of the SOC responsive to detecting the selected events.

System on a chip (SOC) debug controllability

A delay locked loop (DLL) having an accelerated training interval during a voltage change. An integrated circuit (IC) includes a master DLL configured to generate a clock signal based upon a reference clock signal. The master DLL may train to the reference clock signal in response to a control signal. The IC also includes a control unit that is coupled to the master DLL and may provide the control signal at a first interval in response to receiving an indication that a supply voltage is being changed, and provide the control signal at a second interval in the absence of the indication.

DLL having a different training interval during a voltage change

Transmitters generating rotating laser beams are commonly employed for surveying and earth working equipment control purposes. This invention relates to a method and apparatus for automatically maintaining the rotating laser beam in a required plane which is either exactly horizontal or at a known angle to the horizontal. The apparatus includes two remotely located laser beam reflectors which, when traversed by the rotating laser beam, respectively reflect the beam back to the transmitter along a path parallel to, but vertically displaced from the original path of the beam from the transmitter. Receiving equipment at the transmitter analyzes the vertical positions of the two reflected beams and effects any required correction of the position of the transmitter to maintain the rotating laser beam in the desired plane.

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San Jose, CA, United States of America

James D Ramsay