Key Word List

Key Words with Descriptions
Key Word	Description
ALSO	Chains together RETRIEVE, FORMAT or VERIFY statements
ALWAYS_ASK	Used in conjunction with the PARAMETER keyword. Forces the user to enter the parameter every time the decoder is loaded.
APPEND_ONLY	Used in conjunction with TABLE. Causes the protocol stack to automatically traverse to your protocols and use your custom decoders when relevant.
APPEND_AND_OVERWRITE	Used in conjunction with TABLE. Causes the protocol stack to automatically traverse to your protocols but will overwrite table properties. Use with caution.
ASK_IF_NOT_DEFINED	Used in conjunction with the PARAMETER keyword. Asks the user for the parameter the first time the decoder is loaded, and doesn't ask again after that.
BRANCH	Causes control to pass to one of several places depending on the results of the Branch method.
BYTE_STREAM_FRAMER	Reference section keyword followed by a byte stream framer method. Works in a similar fashion to a frame recognizer, except that it operates only on the data found at the current layer.
COUNT	Used with REPEAT clauses to repeat the group X number of times.
DECODE	Begins the decoder.
DEFAULT	Specifies the default entry for tables.
ELSE_SKIP	Used with a Size method to skip a specified amount of data if a conditional fails. If the ELSE_SKIP is not present, no data is skipped.
END_MAIN_PATH	Ends the decoder. At this statement decoding of this layer stops.
ENDTABLE	Specifies the end of a table.
FIELD	The main component of the decoder.
FRAME_AFTER_DECODING	Reference section keyword followed by a frame transformer method that processes the frame after it has been decoded.
FRAME_BEFORE_DECODING	Reference section keyword followed by a frame transformer method that processes the frame before it is decoded.
FIXED	In a FIELD will return a fixed number of bit, bytes, or other units specified.
GROUP	Used to group together FIELDs for a variety of reasons. Groups can be the destination of a branch, they can have conditionals placed on them or REPEAT clauses such that the fields in the group are executed multiple times.
HOST_DATA_ORDER	Can be placed either after the decoder ID at the top of the decoder, in which case all fields are interpreted in host data order, or at the end of a field statement, in which case just that field is interpreted in host data order. See "The Header Section" for more information.
IF	Conditional. Used with Boolean methods.
IGNORE_BRANCH_FIELDS	This lets you use a table across multiple decoders without bringing in all of the DecoderScript to satisfy the Branch fields in TABLEs.
IN_COLLAPSED	Places the results of the field just in the summary line of a collapsed protocol in the Protocol Navigator.
IN_SUMMARY	Places the results of the field in the Summary pane on the Frame Display and in the summary line of a collapsed protocol in the Protocol Navigator.
IN_SUMMARY_ONLY	Places the results of the field in just the Summary pane on the Frame Display
INCLUDE	Inserts the named file at this location in the decoder.
INCLUDE_IF_EXISTS	Inserts the named file at this location in the decoder if the file exists, otherwise it is not included.
INFO	Causes the field output to be displayed in an Information line at the top of the Decode pane in addition to its normal location in the decode.
LIST	Defines a list of legal values that a parameter can take. Used in conjunction with the PARAMETER keyword.
MARGIN_TEXT	Causes the field output to be appended to the margin text in the Protocol Navigator.
NETWORK_DATA_ORDER	Can be placed either after the decoder ID at the top of the decoder, in which case all fields are interpreted in network data order, or at the end of a field statement, in which case just that field is interpreted in network data order. See "The Header Section" for more information.
NEVER_ASK	Used in conjunction with the PARAMETER keyword. Never asks the user for the parameter value. Useful when the parameter has a good default value that may need to be changed only rarely.
NEXT_PROTOCOL	Reference section keyword followed by a Next Protocol method. Determines the next protocol in the stack.
NEXT_PROTOCOL_OFFSET	Reference section keyword followed by a Next Protocol Offset method. Determines the number of bytes between the end of the current layer and the beginning of the next.
NEXT_PROTOCOL_SIZE	Reference section keyword followed by a Next Protocol Size method. Determines the size of the next layer in bytes.
NO_MOVE	Tells the protocol analyzer not to move the bit pointer after decoding the field.
NOT	Reverses the results of a Boolean or Verify method. Often used in IF clauses.
PARAMETER	Defines a runtime parameter for the decoder. Allows the user to give information to the decoder that can be used for decision making or for field definitions.
PAYLOAD_IS_BYTE_STREAM	Reference section keyword. Tells the next protocol in the stack to treat the payload of all subsequent frames as a continuous byte stream. Used in conjunction with the BYTE_STREAM_FRAMER keyword.
POSTPROCESSING	Reference section keyword followed by a method that does things after the layer is decoded. Note that these methods cannot change the data in the frame.
PREPROCESSING	Reference section keyword followed by a method that does things before the layer is decoded. Note that these methods cannot change the data in the frame.
PROCESSING	Allows you to gain control when the frame is first compiled and is useful on frames larger than 64 bits. PROCESSING clauses can be strung together.
PRINT_IF	Followed by a Boolean method. Prints the value of the field in the Decode pane only if the method returns true.
RECOGNIZER	Reference section keyword. Identifier the frame recognizer for the protocol.
REPEAT	Followed by a SIZE, COUNT or UNTIL keyword. Used with groups to cause the group to be repeated.
RESERVED	Used with Size methods to skip a specified amount of data.
RETRIEVE	Used with Retrieve methods, which usually manipulate the contents of the field before displaying it.
SIZE	Followed by a Size method. Used with the REPEAT keyword on groups to repeat the group until the number of bits specified in the Size method have been used up.
START_BIT	Followed by a Start bit method to alter the location of the bit pointer.
STORE	Followed by a name. Stores the field contents under this name so other methods can reference it.
SUMMARY_COLUMNS	Followed by a list of Summary Pane Column names and their default widths. Allows you to define the order of the Summary Pane entries.
SUPPRESS_DETAIL	Prevents the field from being displayed in the Decode pane.
SUPPRESS_IF_VERIFIED	Prevents the field from being displayed in the Decode pane only if the Verify passes. The field is shown if the Verify fails.
TABLE	Begins a table.
TAG	Followed by a Tag method. Used to tag a field for filtering, tracking and other purposes.
TRUNCATED_FIELD_OK	Suppresses an error if a group is truncated, usually an indication of a faulty decoder or damaged frame.
UNTIL	Followed by a Boolean method. Used with the REPEAT keyword on groups to repeat the group until the Boolean method returns true.
VERIFY	A clause placed at the end of FIELD statement to compare the field value with a constant using for example FieldIs or FielsIsBetween.

ALSO

Chains together RETRIEVE, FORMAT or VERIFY statements

ALWAYS_ASK

Used in conjunction with the PARAMETER keyword. Forces the user to enter the parameter every time the decoder is loaded.

APPEND_ONLY

Used in conjunction with TABLE. Causes the protocol stack to automatically traverse to your protocols and use your custom decoders when relevant.

APPEND_AND_OVERWRITE

Used in conjunction with TABLE. Causes the protocol stack to automatically traverse to your protocols but will overwrite table properties. Use with caution.

ASK_IF_NOT_DEFINED

Used in conjunction with the PARAMETER keyword. Asks the user for the parameter the first time the decoder is loaded, and doesn't ask again after that.

BRANCH

Causes control to pass to one of several places depending on the results of the Branch method.

BYTE_STREAM_FRAMER

Reference section keyword followed by a byte stream framer method. Works in a similar fashion to a frame recognizer, except that it operates only on the data found at the current layer.

COUNT

Used with REPEAT clauses to repeat the group X number of times.

DECODE

Begins the decoder.

DEFAULT

Specifies the default entry for tables.

ELSE_SKIP

Used with a Size method to skip a specified amount of data if a conditional fails. If the ELSE_SKIP is not present, no data is skipped.

END_MAIN_PATH

Ends the decoder. At this statement decoding of this layer stops.

ENDTABLE

Specifies the end of a table.

FIELD

The main component of the decoder.

FRAME_AFTER_DECODING

Reference section keyword followed by a frame transformer method that processes the frame after it has been decoded.

FRAME_BEFORE_DECODING

Reference section keyword followed by a frame transformer method that processes the frame before it is decoded.

FIXED

In a FIELD will return a fixed number of bit, bytes, or other units specified.

GROUP

Used to group together FIELDs for a variety of reasons. Groups can be the destination of a branch, they can have conditionals placed on them or REPEAT clauses such that the fields in the group are executed multiple times.

HOST_DATA_ORDER

Can be placed either after the decoder ID at the top of the decoder, in which case all fields are interpreted in host data order, or at the end of a field statement, in which case just that field is interpreted in host data order. See "The Header Section" for more information.

IF

Conditional. Used with Boolean methods.

IGNORE_BRANCH_FIELDS

This lets you use a table across multiple decoders without bringing in all of the DecoderScript to satisfy the Branch fields in TABLEs.

IN_COLLAPSED

Places the results of the field just in the summary line of a collapsed protocol in the Protocol Navigator.

IN_SUMMARY

Places the results of the field in the Summary pane on the Frame Display and in the summary line of a collapsed protocol in the Protocol Navigator.

IN_SUMMARY_ONLY

Places the results of the field in just the Summary pane on the Frame Display

INCLUDE

Inserts the named file at this location in the decoder.

INCLUDE_IF_EXISTS

Inserts the named file at this location in the decoder if the file exists, otherwise it is not included.

INFO

Causes the field output to be displayed in an Information line at the top of the Decode pane in addition to its normal location in the decode.

LIST

Defines a list of legal values that a parameter can take. Used in conjunction with the PARAMETER keyword.

MARGIN_TEXT

Causes the field output to be appended to the margin text in the Protocol Navigator.

NETWORK_DATA_ORDER

Can be placed either after the decoder ID at the top of the decoder, in which case all fields are interpreted in network data order, or at the end of a field statement, in which case just that field is interpreted in network data order. See "The Header Section" for more information.

NEVER_ASK

Used in conjunction with the PARAMETER keyword. Never asks the user for the parameter value. Useful when the parameter has a good default value that may need to be changed only rarely.

NEXT_PROTOCOL

Reference section keyword followed by a Next Protocol method. Determines the next protocol in the stack.

NEXT_PROTOCOL_OFFSET

Reference section keyword followed by a Next Protocol Offset method. Determines the number of bytes between the end of the current layer and the beginning of the next.

NEXT_PROTOCOL_SIZE

Reference section keyword followed by a Next Protocol Size method. Determines the size of the next layer in bytes.

NO_MOVE

Tells the protocol analyzer not to move the bit pointer after decoding the field.

NOT

Reverses the results of a Boolean or Verify method. Often used in IF clauses.

PARAMETER

Defines a runtime parameter for the decoder. Allows the user to give information to the decoder that can be used for decision making or for field definitions.

PAYLOAD_IS_BYTE_STREAM

Reference section keyword. Tells the next protocol in the stack to treat the payload of all subsequent frames as a continuous byte stream. Used in conjunction with the BYTE_STREAM_FRAMER keyword.

POSTPROCESSING

Reference section keyword followed by a method that does things after the layer is decoded. Note that these methods cannot change the data in the frame.

PREPROCESSING

Reference section keyword followed by a method that does things before the layer is decoded. Note that these methods cannot change the data in the frame.

PROCESSING

Allows you to gain control when the frame is first compiled and is useful on frames larger than 64 bits. PROCESSING clauses can be strung together.

PRINT_IF

Followed by a Boolean method. Prints the value of the field in the Decode pane only if the method returns true.

RECOGNIZER

Reference section keyword. Identifier the frame recognizer for the protocol.

REPEAT

Followed by a SIZE, COUNT or UNTIL keyword. Used with groups to cause the group to be repeated.

RESERVED

Used with Size methods to skip a specified amount of data.

RETRIEVE

Used with Retrieve methods, which usually manipulate the contents of the field before displaying it.

SIZE

Followed by a Size method. Used with the REPEAT keyword on groups to repeat the group until the number of bits specified in the Size method have been used up.

START_BIT

Followed by a Start bit method to alter the location of the bit pointer.

STORE

Followed by a name. Stores the field contents under this name so other methods can reference it.

SUMMARY_COLUMNS

Followed by a list of Summary Pane Column names and their default widths. Allows you to define the order of the Summary Pane entries.

SUPPRESS_DETAIL

Prevents the field from being displayed in the Decode pane.

SUPPRESS_IF_VERIFIED

Prevents the field from being displayed in the Decode pane only if the Verify passes. The field is shown if the Verify fails.

TABLE

Begins a table.

TAG

Followed by a Tag method. Used to tag a field for filtering, tracking and other purposes.

TRUNCATED_FIELD_OK

Suppresses an error if a group is truncated, usually an indication of a faulty decoder or damaged frame.

UNTIL

Followed by a Boolean method. Used with the REPEAT keyword on groups to repeat the group until the Boolean method returns true.

VERIFY

A clause placed at the end of FIELD statement to compare the field value with a constant using for example FieldIs or FielsIsBetween.