DAP Technology 1394, Руководство по эксплуатации

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Filter/Trigger
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In the Header Values box, you can specify conditions for header fields. Only packets for which the
specified conditions are met will fit the set. The table in this box shows all possible fields that can be
present in a 1394 packet header. Only those fields that are present in the selected packet types will be
enabled. You can only specify conditions for those enabled fields. If more packet types are selected, only
those fields will be enalbed that are present in all the selected types.
In the example above for instance, the Write Block Request and Read Block Response packet types are
selected and thus only those fields in the Header Values table are enabled that are present in both of
these packet types.
For each enabled field you can specify a value and you can select if the value in the packet should be
equal (==), not equal (!=), less than or equal (<=) or greater than or equal (>=) the value specified in tha
table. In the example above for instance the packet will only fit the set if its Destination field is 0xFFC1
and the Data Length field is 32.
Additionaly you can specify a Mask value per field. This is a bit mask that (when defined) will be applied
to the packet field value and table field value before the field will be compared. For instance if you are
only interrested in the lower 6 bits of the Destination field you could specify a Mask value of 0x003F.
Using the Data Values box, you can specify condtions for data fields. Only packets for which the specified
conditions are met will fit the set. A powerfull packet editor is used to be able to specify conditions for a
large number of possible packets. You have to specify a format for the packet payload data in the Payload
tab. In the example below the 'SBP - CommandOrb' format has been selected. This is a packet format
used for the SBP2 protocol.
The fields in the table show the fields for the payload of this packet format. You can put conditions on
these values just as could be done with the header fields. If the format of a packet depends on the value
of one of its fields, the format will automatically be adjusted if you change the value of that field.
The last field in the example table above is 'command:'. Each SBP CommandOrb packet has a 12 byte
command. There are a lot of possible command formats, and therefore the format of this command can
be selected by a sub format. For parts in a format that are formatted by a sub format, a tab will be added.
In the example above we see the command tab to the right of the Payload tab.
Selecting this tab will show the formatted command, see the example below. Here you can select a sub
format for the command. In the example below the 'SBP - SCSI:Simplified direct-access (RBC) -
command' format is selected.