Synchronized Error Injection
Original Publication Date: 1981-Oct-01
Included in the Prior Art Database: 2005-Feb-12
In the testing of contemporary I/O processors shared by multiple I/O channels (such processors also called directors) it is desirable to be able to establish error states in synchronism with central processor execution of I/O-related functions (acceptance of I/O interruption or execution of an I/O instruction), whereby the effectiveness of retry facilities in the director can be evaluated. For this purpose a reloadable control store in the director, which contains control word microprograms for operating the director, may be loaded with a special DIAGNOSE control word (DOCW) for initiating a Synchronized Error Injection mode of operation in the director. This control word and the associated mode of operation are described below.