Control system for the Texas Experimental Tokamak ECRH system

The electron-cyclotron-resonance heating (ECRH) system for the Texas Experimental Tokamak (TEXT) is being expanded to include three 200 kW gyrotrons. A fourth, half-megawatt gyrotron is to be added in the future. A personal computer is used to control the gyrotrons and their power supplies. The main part of the control system is based on two PC/AT-compatible computers and hardware that interfaces them to the equipment being controlled. One of the computers merely drives a second display screen as a slave to the program running on the master computer. The slave computer is identical to the master computer except for the extra boards the master contains, and either computer alone (with boards swapped if necessary) could operate the system with only display space reduced. The computers are tied together with MetraByte PDMA-16 parallel input/output boards. The computer software and the control system´s data logger are described. System documentation is discussed along with project status