A circuit and method for verifying the operation of error checking circuitry. In one example, a circuit includes a memory, a first error checking circuit, a second error checking circuit, and a comparison circuit. The memory includes a data output. The first error checking circuit includes an input and an output. The input of the first error checking circuit is coupled to the data output of the memory. The second error checking circuit includes an input and an output. The input of the second error checking circuit is coupled to the data output of the memory. The comparison circuit includes a first input and a second input. The first input is coupled to the output of the first error checking circuit. The second input is coupled to the output of the second error checking circuit.

Lockstep comparators and related methods are described. An example apparatus includes self-test logic circuitry having first outputs, and comparator logic including selection logic having first inputs and second outputs, ones of the first inputs coupled to the first outputs, first detection logic having second inputs and third outputs, the second inputs coupled to the second outputs, second detection logic having third inputs and fourth outputs, the third inputs coupled to the third outputs, latch logic having fifth inputs and fifth outputs, the third output and the fourth output coupled to the fifth inputs, and error detection logic having sixth inputs coupled to the fifth inputs.

The present disclosure describes example service takeover methods, storage devices, and service takeover apparatuses. In one example method, when a communication fault occurs between two storage devices in a storage system, the two storage devices respectively obtain running statuses of the two storage devices. A running status can reflect current usage of one or more system resources of a particular storage device. Then, a delay duration is determined according to the running statuses, where the delay duration is a duration for which the storage device waits before sending an arbitration request to a quorum server. The two storage devices respectively send, after the delay duration, arbitration requests to the quorum server to request to take over a service. The quorum server then can select a storage device in a relatively better running status to take over a host service.

A method for managing communications involving a lockstep processing comprising at least a first processor and a second processor can include receiving, at a data synchronizer, a first signal from a first device. The method can also include receiving, at the data synchronizer, a second signal from a second device. In addition, the method can include determining, by the data synchronizer, whether the first signal is equal to the second signal. When the first signal is equal to the second signal, the method can include transmitting, by the data synchronizer, the first signal to the first processor and the second signal to the second processor. Specifically, in example embodiments, transmitting the first signal to the first processor can occur synchronously with transmitting the second signal to the second processor.

A method tests at least three devices, each device including a test chain having a plurality of positions storing test data. The testing includes comparing test data in a last position of the test chain of each of the devices, and shifting test data in the test chains of each of the devices and storing a result of the comparison in a first position of the test chains of each of the devices. The comparing and the shifting and storing are repeated until all the stored test data has been compared. The at least three devices may have a same functionality and a same structure.

A method tests at least three devices, each device including a test chain having a plurality of positions storing test data. The testing includes comparing test data in a last position of the test chain of each of the devices, and shifting test data in the test chains of each of the devices and storing a result of the comparison in a first position of the test chains of each of the devices. The comparing and the shifting and storing are repeated until all the stored test data has been compared. The at least three devices may have a same functionality and a same structure.

A circuit and method for verifying the operation of error checking circuitry. In one example, a circuit includes a memory, a first error checking circuit, a second error checking circuit, and a comparison circuit. The memory includes a data output. The first error checking circuit includes an input and an output. The input of the first error checking circuit is coupled to the data output of the memory. The second error checking circuit includes an input and an output. The input of the second error checking circuit is coupled to the data output of the memory. The comparison circuit includes a first input and a second input. The first input is coupled to the output of the first error checking circuit. The second input is coupled to the output of the second error checking circuit.

A resilient system implementation in a network-on-ship with at least one functional logic unit and at least one duplicated logic unit. A resilient system and method, in accordance with the invention, are disclosed for detecting a fault or an uncorrectable error and isolating the fault. Isolation of the fault prevents further propagation of the fault throughout the system. The resilient system includes isolation logic or an isolation unit that isolates the fault.

A circuit and method for verifying the operation of error checking circuitry. In one example, a circuit includes a memory, a first error checking circuit, a second error checking circuit, and a comparison circuit. The memory includes a data output. The first error checking circuit includes an input and an output. The input of the first error checking circuit is coupled to the data output of the memory. The second error checking circuit includes an input and an output. The input of the second error checking circuit is coupled to the data output of the memory. The comparison circuit includes a first input and a second input. The first input is coupled to the output of the first error checking circuit. The second input is coupled to the output of the second error checking circuit.

A monitoring method includes: performing, by a first arithmetic and logic unit of an electronic circuit unit, a first processing rule to obtain a first processing result, performing, by a second arithmetic and logic unit of an electronic circuit unit, a second processing rule to obtain a second processing result, and, using a protection module of a safety area of the electronic circuit unit, identifying an error-free state of the electronic circuit unit in response to the first and second results having a predefined relationship to each other and/or the first and second results having a predefined relationship to a predefined criterion, where the protection module is configured to ensure that algorithms are carried out in a manner that is better protected from an incorrect execution than the first and second arithmetic and logic units.