BRANCH FACILITY DIAGNOSTICS

摘要

Diagnostic hardware and a method for diagnosis and confidence testing of ROM branching capabilities. Logical circuitry including an RIT flip-flop, which when set modifies the operation of a halt "HLT" micro-op which normally stops the clock, so that the halt "HLT" micro-op will not stop the clock and its absence or the presence of any other micro-op will stop the clock. Execution of any of a predetermined set of branch micro-instructions to predetermined memory locations, sets the RIT flip-flop and causes a branch to a location containing a "HLT." If branching operates properly, the program continues; if not the machine halts, thus identifying the error and avoiding loss of control of the machine.