asynchronous computer[ā′siŋ·krə·nəs kəm′pyüd·ər]
a digital computer in which the beginning of the performance of each operation is determined by the termination signal of the previous operation. Asynchronous computers possess variable time cycles, the magnitude of which is dependent on the length of the operation. The asynchronous principle provides the machine with a comparatively high speed of computation and permits sufficiently simple coordination of the operation of units with different response speed. In addition, it creates a certain self-control in the machine, in that the machine stops when some operation is not performed or the signal concerning its termination is not received. Asynchronous computers can be partially asynchronous; the asynchronous principle is used only for the performance of those operations whose duration is considerably longer than the time of access to the operative storage device (for example, multiplication, division, input of information, and so on), and the remaining operations have a constant operation cycle.