公开(公告)号：DE2460011A1

公开(公告)日：1975-07-10

申请号：DE2460011

申请日：1974-12-19

Applicant: IBM

Inventor： LEWIS DAVID OTTO ,  MILLER THOMAS HOWARD ,  SCHMITT STEVEN ALOI

IPC: G06F3/00 ,  G06F13/10 ,  G06F9/00

Abstract: A computer system executes instructions for an I/O device not attached to the system. A quasi I/O attachment device is responsive to the commands for the unattached I/O device and generates an interrupt condition. The interrupt condition causes the command instructions for the unattached I/O device to be translated to command instructions for an I/O device connected to the computer system. The I/O device attached to the system performs the designated operation and generates associated I/O device status data. This associated I/O device status data is translated into I/O device status data for the unattached I/O device and thus permits a program for operating an unattached I/O device to operate instead an I/O device attached to the system which otherwise could not be operated by that program. A second embodiment performs the emulation of the unattached I/O device remotely of the central processing unit in the computer system.