Freescale Semiconductor, Inc.

MMDS Target Component

4.10 Bus Analyzer

4.10.1.1 Watchpoints

The MMDS0508 automatically maps available watchpoints to a proper bus analyzer trigger pattern. You may use the bus analyzer to implement watchpoints. If you do, however, you should not use the bus analyzer for other purposes!

4.10.1.2 Trace Modes

To gather pertinent bus data, you can operate the bus analyzer in different modes. The various trace modes let you choose appropriate actions to take when a certain pattern (event), or sequence of patterns, appears on the bus. To trigger the Bus analyzer, define specific bus states as terms, and select a sequence of terms as a trigger event.

4.10.1.3 Trace Buffer

The trace buffer consists of 8,192 entries (or frames), each of which stores 96 bits. When the bus analyzer is active and the emulator is running, the system strobes a frame of the selected type into the trace buffer for each bus cycle. When trigger events occur in a specified sequence, the system stores only the specified number of additional frames.

4.10.1.4 Textual or Graphical

The bus analyzer displays data either textually or graphically. Use the horizontal and vertical scroll bars, as in other Windows applications, to move around the displays.

4.10.2 Using the Bus Analyzer

The bus analyzer functions like any debugger component, and has its own menu to control the features of the MMDS0508 Bus analyzer hardware. Another name for the Bus Analyzer window is the Trace window. This is because the bus analyzer corresponds to the trace component; you can load the bus analyzer by choosing Open... Trace from the Component menu. Choose the MMDS0508 menu, then select Bus Trace to open the Trace window (show in Figure 4.16) or the Bus Analyzer (shown in Figure 4.15).

The three steps to using the Bus analyzer are: defining the data collection parameters, collecting the specified bus data (running the program), and viewing the collected data.

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MMDS0508 Target Interface

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Freescale Semiconductor MMDS0508 Using the Bus Analyzer, Watchpoints, Trace Modes, Trace Buffer, Textual or Graphical