A prototype switched Ethernet data acquisition system

A prototype switched Ethernet data acquisition system has been built up and successfully operated in HL-1M tokamak experiments. The system is based on a switched high bandwidth Ethernet network with which the CAMAC crates are directly interfaced. It takes the advanced features of LAN switch and Ethe rnet CAMAC controller (ECC 1365 MK III, HYTEC product) to avoid the rewriti ng of CAMAC driver for an individual computer system and to ensure high dat a transmission rate between CAMAC system and host computers on the network. It is a new approach to DAS system architecture and provides a solution fo r a well-known bottleneck problem in traditional distributed DAS system for fusion research. An average throughput of the test system reaches over 100 Mbps. The system features also an easy and low cost migration from traditi onal distributed DAS system. In the paper, the hardware configuration, soft ware structure, performance of the system and the method of migrating from current DAS system are discussed in detail. (C) 1999 Elsevier Science S.A. All rights reserved.