Design Of Remote Control Software Of The LXI Trigger Box And Study On Synchronization Algorithm

As a result of the rapid development and popularization of the Ethernet technology in recent years, technology of LXI bus has been widely used to the test and measurement applications. The adaptability of high-speed LAN interface and the unified model of trigger and the timing characteristics of IEEE1588, simplify the integration of the test systems and reduce the cost for design and maintenance, provide better options for the test system builders. LXI bus has been supported by most of the equipment manufacturers, and will gradually replace other traditional test bus technology, such as GPIB, VXI and so on.This thesis is based on the project of "LXI class A Trigger box". The LXI trigger box conforms to LXI class A standard, which can be accessed through the network, supports the IEEE1588 synchronization protocol, and supports the hardware bus trigger mode. The LXI trigger box also makes non-LXI instruments compatible with LXI instruments via TTL pulse output. The LXI trigger box has the function of controlling instruments with RS-232 interface remotely, which enables the traditional RS-232 instruments to be controlled through network.In this thesis the LXI trigger box remote control software is designed and implemented. The accuracy of PTP synchronization is improved and multi-device synchronization is implemented. Contributions are as follows:1. The C/S software and B/S software of the remote control function are designed and implemented. The C/S software includes the SCPI commands and instrument drivers. The B/S software includes Web interfaces and server programs.2. A LXI platform based on LXI trigger box and LabWindows/CVI environment is built.3. The factors that affect synchronization effects are analyzed. The accuracy of synchronization is improved by using PI controller tuning programs. A scheme of timestamp matching based on the FIFO is proposed and the accuracy of multiple device synchronization of the LXI trigger box is improved.The thesis includes the test of the remote control software and IEEE1588 synchronization accuracy. Test results show that the function of remote controlling software is implemented. The PTP synchronization accuracy is improved. The maximum deviation is 20 ns when the boxes are connected by a network cable directly. The maximum deviation is 70 ns when the boxes are synchronized through a switch which supports the PTP protocol. The maximum deviation is 300 ns when the boxes are synchronized through an ordinary switch.