Composition (Digital Input)

Menu Path: Input > Digital

A Logic Analyzer can have multiple input modules. For each module, individual bit inputs are grouped into named buses. There can also be one or more software Tools associated with a module in the Logic Analyzer configuration. Tools receive data from module data buses and transform it into one or more output buses. Data from buses at the outputs of either modules or Tools can be composed into input data streams for the VSA.

The VSA expects either real or complex data. Complex data has two parts, represented as either I and Q (real and imaginary) or magnitude and phase. These parts can either be interleaved on a single data bus or transmitted in parallel on two separate buses.

Within the composition group, a Module Name is chosen first. The Parts property selects the data representation (real, rectangular complex, or polar complex). The Module Name and Parts selections are common to all channels. If the Logic Analyzer configuration includes supported Tools at the output of any module, the Tool Names property selects a Tool or “none”. Select "none" if the data is to be input directly from the hardware module. Finally, select the Bus Name used for each Part of the data. The Tool Name and Bus Name properties are channel specific, each property must be assigned to a channel.

When the VSA is initially connected to a Logic Analyzer, the VSA attempts to create a reasonable default setup based on the detected input module. For any connected module with buses named I and Q, the composition properties are set to that module name and the I and Q bus names are specified to supply real and imaginary data.