US Patent:
20120239368, Sep 20, 2012
Inventors:
Nimrod Agmon - Sunnyvale CA, US
International Classification:
G06G 7/62
G06F 9/30
US Classification:
703 13, 712220, 712E09016
Abstract:
In an embodiment, the design of a digital circuit may be analyzed to identify which uninitialized memory elements, such as flops, have initial don't care values. The analysis may include determining that that each possible initial value (e.g. zero and one) of the flops does not impact the outputs of circuitry to which the uninitialized flops are connected. For example, a model may be generated that includes two instances of the uninitialized flops and corresponding logic circuitry. The inputs of the two instances may be connected together, and the uninitialized flops may be initialized to zero in one instance and one in the other instance. If the outputs of the two instances are equal for any input stimulus, the initial value of the uninitialized flops may be don't cares. The flops may be safely initialized to a known value for simulation.