As described in Window and Streaming Data API in AI Engine Kernel and Graph Programming Guide (UG1079), the data flows into and out of an AI Engine kernel through access windows, or a stream interface. During debug you might want to see the value of these data access windows as data is passing through the kernels. In the following figure you can trace the series of objects that you must work through to examine the contents of the variables.
Figure 1. Data Access Chain