摘要 |
A microinstruction error is detected in a microprogrammed digital data processor by providing for checking the presence of an error in an accessed microinstruction concurrently with the application of the accessed microinstruction to the microprocessor execution unit. If a microinstruction error is detected, microinstruction execution is aborted and a maintenance processor provides a correct microinstruction, following which operations are restarted. Provision is also made for detecting whether the error is a hard error and, if so, for substituting a spare microinstruction memory for the memory portion which caused the hard error. |