Patent ID: 7716034
Filing Date: 2010-05-11
Classification: G06F

Abstract:
1. A trace data compression apparatus in a trace system capable of receiving trace data on a first port and a second port comprising: a prior data register storing a prior data value; a first comparator having a first input receiving trace data on said first port and a second input connected to said prior data register, said first comparator comparing respective equal length sections of said trace data currently received on said first port with said stored prior data value and generating a first compression map having individual bits corresponding to said respective equal length sections, each individual bit having a first digital state if said respective equal length sections match and a second opposite digital state if said respective equal length sections do not match; a second comparator having a first input receiving trace data on said second port and a second input connected to said prior data register, said second comparator comparing respective equal length sections of said trace data currently received on said second port with said stored prior data value and generating a second compression map having individual bits corresponding to said respective equal length sections, each individual bit having a first digital state if said respective equal length sections match and a second opposite digital state if said respective equal length sections do not match; a third comparator having a first input receiving trace data on said first port and a second input receiving trace data on said second port, said third comparator comparing respective equal length sections of said trace data currently received on said first port with said trace data currently received on said second port and generating a third compression map having individual bits corresponding to said respective equal length sections, each individual bit having a first digital state if said respective equal length sections match and a second opposite digital state if said respective equal length sections do not match; a trace data selection apparatus receiving trace data on said first port, a receiving trace data on said second port and connected to said first, second and third comparators, said trace data selection apparatus operative to