Many DOS application programs, including our own, have grown to the point where new features cannot be added due to the 640-kbyte DOS limitation. Virtual memory is not desired for real-time work, since we do not want the application to wait until it can be swapped back into memory from the disk. Therefore, it is important that this feature can be disabled and that performance is maintained when it is disabled. If there is a problem in software under development, instead of crashing, the operating system simply informs the operator of an attempt to violate protection and then terminates the program. ONLY does a multitasking computer operating system allow different applications to run simultaneously, it also allows multiple copies of the same application to be run together.
Reactors typically run for extended lengths of time and are independently operated.
One way to provide computer control for these reactors is to have individual computers and peripherals for each reactor. However, this is very expensive, both in actual costs and in lab bench space. Each control system can be started, stopped, and operated independently. Thus, a single computer system can provide all the functionality of separate systems for each reactor. In these cases, the interrupt latency is nonlimiting because the CPU is not involved in the acquisition of data or the transfer of data into memory.