S/370 Control Unit Simulator
Original Publication Date: 1987-Feb-01
Included in the Prior Art Database: 2005-Jan-31
A control unit simulator (CUS) tests channel functions in IBM System/ 370 processors in an automated test environment. The CUS works in the following manner. The CUS is a mode-controlled test device which operates in any S/370 channel. A six-card simulator contains the necessary logic to simulate an input/output (I/O) control unit and 8K of high speed RAM to simulate a storage medium (Fig. 1). A control register is set via a code which provides the means of selecting any mode and its design options. The CUS can only test one channel at a time, but the CUS can be switched to eight different channels, as seen in the CUS switching group in Fig. 2. Two simulators are placed in a switch group as a back-up for each other.