TRANSFER DEVICE OF INPUT AND OUTPUT DATA

PURPOSE:To attain the transfer of input/output data with a small quantity of hardware and a short input/output overhead time, by setting plural window buffers to each I/O and therefore eliminating the idle control. CONSTITUTION:Window buffers 60, 62 and 64 are set to I/Os 311, 312 and 313 respectively. Thus the idle control can be omitted to each I/O since these I/O use exclusively each window buffer. Furthermore these buffers have no loss of main storage owing to increase of window buffers since the correspondence of the main storage is secured in a data transfer mode. If the data transfer requests are given simultaneously to both I/Os 311 and 312, buffers 61 and 63 are secured respectively. Thus data are transferred via these window buffers. This attains the transfer of input/output data with a small quantity of hardware and a short overhead time.