Abstract:
The error tolerant arithmetic logical unit is divided into vertical bit-planes which are relatively independent, being coupled mainly for the purposes of shifts and carry propagation. The system tolerates failures and still functions correctly by reconfiguring the unit through the control of interplane connections. By inserting a spare bit-plane into the system and switching between bit-planes to bypass a failed plane, the effect of the failed plane or of a failure in a position of control logic can be eliminated.
Abstract:
A computer system of the standby redundancy type including three active logic modules and at least one spare module, characterized by the provision of triple modular redundancy means for correcting and locating the failure of a first one of said active logic modules, in combination with sparing means for reconfiguring the system to by-pass the faulty module and to substitute the spare module therefor. The invention is further characterized by the provision of means for reintroducing the first module into the system upon the detection of failure of another active module.
Abstract:
Mapping control means for achieving error toleration in computer addressing circuitry including switching means for connecting an address register with the effective address register of a basic operating module. The switching means are operable by a blocking register and at least one status register to control the mapping connections in a given manner. The invention is characterized by the provision of an address blocking register and a mask register that process a sequence of failed addresses and insert corresponding control instructions in the blocking and status registers so that the switching means dynamically excludes access to the memory area affected by the faulty address circuitry.