SYNCHRONISATION AND TRIGGER DISTRIBUTION ACROSS INSTRUMENTATION NETWORKS

摘要

A system for synchronising the operation of a measurement instrument having a microcontroller, a local oscillator and function circuitry to an external timebase is provided. The system includes a USB Host Controller; an interrupt generator adapted to respond to ITPs by generating respective interrupts and passing the interrupts to the microcontroller; and a timer for measuring an interval between receptions of the ITPs in a time domain of the local oscillator.

主权项

1. An apparatus for transferring trigger signals from a first USB device to a plurality of second USB Devices attached to a USB network with minimal latency, the apparatus comprising:
communication circuitry adapted for communicating upstream toward a USB Host Controller and communicating downstream toward a plurality of USB devices; and trigger engine circuitry adapted to observe communication traffic through said apparatus; wherein said apparatus is adapted to decode upstream directed communication directed to the USB Host Controller from said plurality of USB devices, to search for specific trigger request signals transmitted upstream from said USB network, and to transmit trigger command packets downstream toward said plurality of USB devices upon reception of said trigger request signals, and wherein said trigger command packets are initiated by the apparatus.