JPSA recommends two UV excimer laser control schemes, a ring configuration and a star configuration.
In the ring configuration, each module of the control system possesses a level of intelligence. This distributed intelligence permits the use of simple microprocessors, since multiple single tasking controllers can execute the different tasks that the laser performs simultaneously. The laser control computer typically handles host interface communications and sequences the tasks of the other modules. One disadvantage of the ring configuration is that if one module fails, the entire control system crashes.
In the star configuration, a microprocessor orchestrates all system functions locally. Communications with the other modules can be simple I/O or data communications, but the peripheral systems themselves have no autonomy. If a module fails in this scheme, the control system may still be used to troubleshoot the problem. The main disadvantage of this type of system is the high computational power required to multitask in real time.
