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busTRACE This WEB page comes from the busTRACE 7.0 User's Manual. (Table of Contents)

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You can configure busTRACE to let it know which CDBs you want it to capture or, alternatively, which CDBs you want it to not capture. The CDB Filter is set down in kernel mode and causes the specified CDB requests to be skipped and not captured. This is the key difference from our ability to filter I/O activity from view. When you filter I/O activity from view, the I/O is captured, it is still in memory, it is only filtered from view.

This feature can be useful to save your capture buffer space for only those CDB requests that you are interested in capturing. This feature is only applicable to devices that process CDBs.

You can set a CDB Filter in one of several places

The filter dialog box gives you three options on how you want to create a CDB Filter:

Capture all CDBs except for the following If you select this option, you are configuring busTRACE to capture every CDB opcode that it sees except for the ones that you add to the list. You can add any number of CDBs that you like. Simply click on the Add button to add CDB entries and the Remove button to remove CDB entries.
Capture only the following CDBs If you select this option, you are configuring busTRACE to capture only the CDB opcodes that you list. You can add any number of CDBs that you like. Simply click on the Add button to add CDB entries and the Remove button to remove CDB entries.
Advanced Editor If you select this option, you can type in any boolean equation that you like. See our section below on the Advanced Editor.

When you click on the Add button, you are shown a list of all the available CDB opcodes that you can add to the list. For example:

Simply select the CDB opcode that you would like to add to your list and then click on the Add button below.

Advanced Editor

As you can see above, it is easy to define which CDB opcodes you want to capture or which ones you do not want to capture. If you choose our Advanced Editor option, you can enter a boolean equation to create any number of possibilities for the CDB filter.

The boolean equation follows 'C' programming constructs. The following examples should help you better understand how to set an advanced mode CDB Filter.

Capture only CDBs with opcode 00h or 12h

(CDB0==00h)||(CDB0==12h)

Capture all CDBs except for opcode 28h and opcode AAh

(CDB0!=28h)&&(CDB0!=28h)

Capture all CDBs with opcode 28h, CDB offset 2 greater than or equal to 20h, and bit 7 of CDB offset 9 set to one and bit 6 of CDB offset 9 set to 0.

(CDB0==28h)&&(CDB2>=20h)&&((CDB9&C0h)==80h)

Capture all CDBs with opcode 88h and CDB offset 13 less than 20h.

(CDB0==88h)&&(CDB13<20h)

See Also: