Teledyne Protocol Analyzers File-Based Decoding User Manual

PROTOCOL SOLUTIONS GROUP

3385 SCOTT BLVD

SANTA CLARA, CA 95054

LeCroy Protocol Analyzers

File-Based Decoding

User Manual

August 2011

Document Disclaimer File-based Decoding User Manual

Document Disclaimer

The information in this document has been carefully checked and is believed to be reliable. However, no responsibility can be assumed for inaccuracies that may not have been detected.

LeCroy reserves the right to revise the information in this document without notice or penalty.

Trademarks and Servicemarks

CATC Trace, FCTracer, SATracer, SASTracer, PETracer, PETracer ML, PETracer EML, UWBTracer, UWBTracer MPI, BTTracer, Merlin, Merlin II, USBTracer, USB USB

Mobile HS, Voyager, Advisor T3, UPAS, and BusEngine are trademarks of LeCroy.

Microsoft and Windows are registered trademarks of Microsoft Inc.

All other trademarks are property of their respective companies.

Mobile,

This document may be printed and reproduced without additional permission, but all copies should contain this copyright notice.

LeCroy Corporation

File-based Decoding User Manual Table of Contents

TABLE OF CONTENTS

Chapter 1 Introduction 1

1.1 Features of CATC Scripting Language. . . . . . . . . . . . . . . . . . . . . . . . . 1

Chapter 2 Values 3

2.1 Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

2.2 Variables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

2.3 Constants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Chapter 3 Expressions 7

3.1 select expression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Chapter 4 Operators 9

4.1 Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

4.2 Operator Precedence and Associativity . . . . . . . . . . . . . . . . . . . . . . . . 9

Chapter 5 Comments 17

Chapter 6 Keywords 19

Chapter 7 Statements 21

7.1 Expression Statements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

7.2 if Statements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

7.3 if-else Statements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

7.4 while Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

7.5 for Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

7.6 return Statements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

7.7 Compound Statements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Chapter 8 Preprocessing 27

Chapter 9 Context 29

Chapter 10 Functions 31

Chapter 11 Primitives 33

11.1 General Primitives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

11.2 Data Manipulation Primitives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

11.3 List Manipulation Primitives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

11.4 Transaction Decoder Primitives . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

11.5 Display Primitives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Appendix A:PCI Express . . . . . . . . . . . . . . . . . . . . . . . . . 59

A.1 Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Module Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

A.2 Decoder Script Files. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

cfg.dec . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

io.dec . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

mem.dec. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

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Appendix B:Bluetooth . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

B.1 Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Module Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Module Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

B.2 Input Context Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

How to Contact LeCroy . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Index 73

iv LeCroy Corporation

File-based Decoding User Manual List of Figures

LIST OF FIGURES

Figure 7.1 Execution of a for Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Figure 11.1 Example: Output for AddCell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Figure 11.2 Example: Output for AddDataCell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Figure 11.3 Example: Separator Cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Figure 11.4 Example: Output for BeginCellBlock with Red Group Collapsed . . . . . . . . 57

Figure 11.5 Example: Output for BeginCellBlock with Red Group Expanded and Blue

Group Collapsed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Figure 11.6 Example: Output for BeginCellBlock with Red Group Expanded and Blue

Group Expanded . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

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List of Tables File-based Decoding User Manual

LIST OF TABLES

Table 2.1 Examples of String Literals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Table 2.2 Escape Sequences. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Table 4.1 Operator Precedence and Associativity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Table 4.2 Operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Table 6.1 Keywords . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

vi LeCroy Corporation

File-based Decoding User Manual Chapter 1: Introduction

Chapter 1: Introduction

CATC Scripting Language (CSL) was developed to create scripts that would allow users to perform file-based decoding with all LeCroy analyzers. CSL is used to edit CATC

Decode Scripting (CDS) files, which are pre-written decoder scripts supplied by LeCroy. These script-based decoders can be modified by users or used as-is. Additionally, users can create brand new CDS files.

This document includes the following analyzer-specific contents:

• Appendix A: PETracer™ Decoder Script Files (for the PETracer product)

• Appendix B: Bluetooth Decoding scripts for analyzers are located in the /Scripts sub-directory below the

application directory. These scripts are tools to decode and display transactions. Users can also add entirely new, customized decoders to fit their own specific development needs. The analyzer application looks in the sub-directories and automatically loads all of the .dec files that it finds. To prevent a particular decoder from being loaded, change its extension to something other than .dec or move it out of the

CSL is based on C language syntax, so anyone with a C programming background should have no trouble learning CSL. The simple, yet powerful, structure of CSL also enables less experienced users to easily acquire the basic knowledge needed to start writing custom scripts.

/Scripts directory.

/Scripts directory and all its

1.1 Features of CATC Scripting Language

• Powerful: Provides a high-level API while simultaneously allowing implementation

of complex algorithms.

• Easy to learn and use: Has a simple but effective syntax.

• Self-contained: Needs no external tools to run scripts.

• Wide range of value types: Provides efficient and easy processing of data.

• Script-based decoding: Used to create built-in script-based decoders for analyz-

ers.

• Custom decoding: May be used to write custom decoders.

• General purpose: Is integrated in a number of LeCroy products.

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Chapter 1: Introduction File-based Decoding User Manual

2 LeCroy Corporation

File-based Decoding User Manual Chapter 2: Values

Chapter 2: Values

There are five value types that may be manipulated by a script: integers, strings, lists, raw bytes, and null. CSL is not a strongly typed language. Value types need not be

re-declared. Literals, variables and constants can take on any of the five value types,

p and the types can be reassigned dynamically.

2.1 Literals

Literals are data that remain unchanged when the program is compiled. Literals are a way of expressing hard-coded data in a script.

Integers

Integer literals represent numeric values with no fractions or decimal points. Hexadecimal, octal, decimal, and binary notation are supported:

Hexadecimal numbers must be preceded by 0x: 0x2A, 0x54, 0xFFFFFF01

Octal numbers must begin with 0: 0775, 017, 0400

Decimal numbers are written as usual: 24, 1256, 2

Binary numbers are denoted with 0b: 0b01101100, 0b01, 0b100000

Strings

String literals are used to represent text. A string consists of zero or more characters and can include numbers, letters, spaces, and punctuation. An empty string ("") contains

o characters and evaluates to false in an expression, whereas a non-empty string

n evaluates to true. Double quotes surround a string, and some standard backslash ( escape sequences are supported.

String Represented Text

"Quote: \"This is a string literal.\""

"256"

"abcd!$%&*"

"June 26, 2001"

"[ 1, 2, 3 ]"

Table 2.1 Examples of String Literals

Quote: "This is a string literal."

256

**Note that this does not represent the

integer 256, but only the characters that make up the number.

abcd!$%&*

June 26, 2001

[ 1, 2, 3 ]

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Chapter 2: Values File-based Decoding User Manual

Escape Sequences

These are the available escape sequences in CSL:

Escape

Character

backslash This is a backslash: \

doub quote

horizon tab

ine This is how

newl

single quote 'Single quote'

Sequence Example Output

\\ "This is a backslash: \\"

\" "\"Quotes!\""

tal

\t "Before tab\tAfter tab"

\n "This is how\nto get a newline."

\' "\'Single quote\'"

"Quotes!"

Before tab After tab

et a newline.

to g

Table 2.2 Escape Sequences

Lists

A list can hold zero or more pieces of data. A list that contains zero pieces of data is called an empty list. An empty list evaluates to false when used in an expression, whereas a non-empty list evaluates to true. List literals are expressed using the square bracket ( delimiters. List elements can be of any type, including lists.

[1, 2, 3, 4] [] ["one", 2, "three", [4, [5, [6]]]]

[])

Raw Bytes

Raw binary values are used primarily for efficient access to packet payloads. A literal notation is supported using single quotes:

'00112233445566778899AABBCCDDEEFF'

This represents an array of 16 bytes with values starting at 00 and ranging up to 0xFF.

e values can only be hexadecimal digits. Each digit represents a nybble (four bits), and

Th if there are not an even number of nybbles specified, an implicit zero is added to the first byte. For example:

'FFF'

is interpreted as

'0FFF'

null

null indicates an absence of valid data. The keyword null represents a literal null value and evaluates to false when used in expressions.

result = null;

4 LeCroy Corporation

File-based Decoding User Manual Chapter 2: Values

2.2 Variables

Variables are used to store information, or data, that can be modified. A variable can be thought of as a container that holds a value.

All variables have names. Variable names must contain only alphanumeric characters and the underscore ( variable names are

x _NewValue name_2

A variable is created when it is assigned a value. Variables can be of any value type, and can change type with re-assignment. Values are assigned using the assignment operator (

= ). The name of the variable goes on the left side of the operator, and the value goes

on the right:

x = [ 1, 2, 3 ] New_value = x name2 = "Smith"

If a variable is referenced before it is assigned a value, it evaluates to null.

There are two types of variables: global and local.

_ ) character, and they cannot begin with a number. Some possible

Global Variables

Global variables are defined outside of the scope of functions. Defining global variables requires the use of the keyword all files that it includes).

set Global = 10;

If an assignment in a function has a global as a left-hand value, a variable is not created, but the global variable is changed. For example:

set Global = 10;

Function() {

Global = "cat"; Local = 20;

}

creates a local variable called Local, which is only visible within the function Function. Additionally, it changes the value of This also changes its value type from an integer to a string.

set. Global variables are visible throughout a file (and

Global to "cat", which is visible to all functions.

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Local Variables

Local variables are not declared. Instead, they are created as needed. Local variables are created either by being in a function's parameter list, or simply by being assigned a value in a function body.

Function(Parameter) {

Local = 20;

}

This function creates a local variable Parameter and a local variable Local, which has an assigned value of 20.

2.3 Constants

A constant is similar to a variable, except that its value cannot be changed. Like variables, constant names must contain only alphanumeric characters and the underscore ( character, and they cannot begin with a number.

Constants are declared similarly to global variables using the keyword const:

const CONSTANT = 20;

_ )

They can be assigned to any value type, but generates an error if used in the left-hand side of an assignment statement later on. For example:

const constant_2 = 3;

Function() {

constant_2 = 5;

}

generates an error.

Declaring a constant with the same name as a global, or a global with the same name as a constant, also generates an error. Like globals, constants can only be declared in the file scope.

6 LeCroy Corporation

File-based Decoding User Manual Chapter 3: Expressions

Chapter 3: Expressions

An expression is a statement that calculates a value. The simplest type of expression is assignment:

x = 2

The expression x = 2 calculates 2 as the value of x.

All expressions contain operators, which are described in Chapter 4, Operators, on page 9. The operators indicate how an expression should be evaluated in order to arrive at its value. For example

x + 2

says to add 2 to x to find the value of the expression. Another example is

x > 2

which indicates that x is greater than 2. This is a Boolean expression, so it evaluates to either true or false. Therefore, if false.

True is denoted by a non-zero integer (any integer except 0), and false is a zero integer (0). True and false are also supported for lists (an empty list is false, while all others are true), and strings (an empty string is false, while all others are true), and considered false. However, all Boolean operators result in integer values.

x = 3, then x > 2 evaluates to true; if x = 1, it returns

null is

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Chapter 3: Expressions File-based Decoding User Manual

3.1 select expression

The select expression selects the value to which it evaluates based on Boolean expressions. This is the format for a

select {

<expression1> : <statement1> <expression2> : <statement2> ...

};

The expressions are evaluated in order, and the statement that is associated with the first true expression is executed. That value is what the entire expression evaluates to.

x = 10 Value_of_x = select {

x < 5 : "Less than 5"; x >= 5 : "Greater than or equal to 5";

};

The above expression evaluates to “Greater than or equal to 5” because the first true expression is expression because it is not a compound statement and can be used in an expression context.

x >= 5. Note that a semicolon is required at the end of a select

select expression:

There is also a keyword default, which in effect always evaluates to true. An example of its use is

Astring = select {

A == 1 : "one"; A == 2 : "two"; A == 3: "three"; A > 3 : "overflow"; default : null;

};

If none of the first four expressions evaluates to true, then default is evaluated, returning a value of

select expressions can also be used to conditionally execute statements, similar to C switch statements:

select {

A == 1 : DoSomething(); A == 2 : DoSomethingElse(); default: DoNothing();

};

In this case the appropriate function is called depending on the value of A, but the evaluated result of the

null for the entire expression.

select expression is ignored.

8 LeCroy Corporation

File-based Decoding User Manual Chapter 4: Operators

Chapter 4: Operators

An operator is a symbol that represents an action, such as addition or subtraction, that can be performed on data. Operators are used to manipulate data. The data being manipulated are called operands. Literals, function calls, constants, and variables can all serve as operands. For example, in the operation

x + 2

the variable x and the integer 2 are both operands, and + is the operator.

4.1 Operations

Operations can be performed on any combination of value types, but results in a null value if the operation is not defined. Defined operations are listed in the Operand Types column of results in the non-null value. For example, if

then

Tab le 4.2 on page 11. Any binary operation on a null and a non-null value

x = null

3 * x

returns a value of 3.

A binary operation is an operation that contains an operand on each side of the operator, as in the preceding examples. An operation with only one operand is called a unary operation, and requires the use of a unary operator. An example of a unary operation is

which uses the logical negation operator. It returns a value of 0.

4.2 Operator Precedence and Associativity

Operator rules of precedence and associativity determine in what order operands are evaluated in expressions. Expressions with operators of higher precedence are evaluated first. In the expression

4 + 9 * 5

the * operator has the highest precedence, so the multiplication is performed before the addition. Therefore, the expression evaluates to 49.

The associative operator () is used to group parts of the expression, forcing those parts to be evaluated first. In this way, the rules of precedence can be overridden.

For example,

( 4 + 9 ) * 5

causes the addition to be performed before the multiplication, resulting in a value of 65.

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Chapter 4: Operators File-based Decoding User Manual

When operators of equal precedence occur in an expression, the operands are evaluated according to the associativity of the operators. This means that if an operator's associativity is left to right, then the operations is done starting from the left side of the expression. So, the expression

4 + 9 - 6 + 5

would evaluate to 12. However, if the associative

operator is used to group a part or parts

of the expression, those parts are evaluated first. Therefore,

( 4 + 9 ) - ( 6 + 5 )

has a value of 2.

In Table 4.1, Operator Precedence and Associativity, the operators are listed in order of precedence, from highest to lowest. Operators on

the same line have equal precedence,

and their associativity is shown in the second column.

Operator Symbol Associativity

++ --

[] ()

~ ! sizeof head tail first next more

Right to left

Left to right

Right to left

last prev

* / %

+ -

<< >>

< > <= >=

== !=

Left to right

= += -= *= /= %= >>= <<= &= ^= |=

Left to right

Right to left

Table 4.1 Operator Precedence and Associativity

10 LeCroy Corporation

File-based Decoding User Manual Chapter 4: Operators

Operator Symbol Description Operand Types

Result Types Examples

Index Operator

[ ] Index or subscript Raw Bytes Integer Raw = '001122'

Raw[1] = 0x11

List Any List = [0, 1, 2, 3, [4, 5]]

List[2] = 2 List[4] = [4, 5] List[4][1] = 5

*Note: if an indexed Raw value is assigned to any value that is not a byte ( variable is promoted to a list before the assignment is performed.

Associative Operator

( ) Associative Any Any ( 2 + 4 ) * 3 = 18

2 + ( 4 * 3 ) = 14

Arithmetic Operators

* Multiplication Integer-integer Integer 3 * 1 = 3

/ Division Integer-integer Integer 3 / 1 = 3

% Modulus Integer-integer Integer 3 % 1 = 0

+ Addition Integer-integer Integer 2 + 2 = 4

String-str ing Strin g "one " + "two" = "one two"

Raw byte-raw byte Raw '001122' + '334455' = '001122334455'

List-list List [1, 2] + [3, 4] = [1, 2, 3, 4]

Integer-list List 1 + [2, 3] = [1, 2, 3]

Integer-string Strin g "number = " + 2 = "number = 2"

*Note: integer-string concatenation uses decimal conversion.

String-lis t List "one" + ["two"] = ["one", "two"]

- Subtraction Integer-integer Integer 3 – 1 = 2

> 255 or not an integer), the

Increment and Decrement Operators

++ Increment Integer Integer a = 1

-- Decrement Integer Integer a = 2

++a = 2

b = 1 b++ = 1

*Note that the value of b after execution is 2.

--a = 1

b = 2 b-- = 2

*Note that the value of b after execution is 1.

Table 4.2 Operators

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Chapter 4: Operators File-based Decoding User Manual

Operator Symbol Description Operand Types

Result Types Examples

Equality Operators

== Equal Integer-integer Integer 2 == 2

String-str ing Integer "three" == "three"

Raw byte-raw byte Integer '001122' == '001122'

List-list Integer [1, [2, 3]] == [1, [2, 3]]

!= Not equal Integer-integer Integer 2 != 3

String-str ing Integer "three" != "four"

Raw byte-raw byte Integer '001122' != '334455'

List-list Integer [1, [2, 3]] != [1, [2, 4]]

Relational Operators

< Less than Integer-integer Integer 1 < 2

String-str ing Integer "abc" < "def"

> Greater than Integer-integer Integer 2 > 1

String-str ing Integer "xyz" > "abc"

<= Less than or equal Integer-integer Integer 23 <= 27

String-str ing Integer "cat" <= "dog"

>= Greater than or

equal

Integer-integer Integer 2 >= 1

String-str ing Integer "sun" >= "moon"

*Note: equality operations on values of different types evaluates to false.

*Note: relational operations on string values are evaluated according to character order in the ASCII table.

Table 4.2 Operators (Continued)

12 LeCroy Corporation

File-based Decoding User Manual Chapter 4: Operators

Operator Symbol Description Operand Types

Result Types Examples

Logical Operators

! Negation All combinations of types Integer !0 = 1 !"cat" = 0

!9 = 0 !"" = 1

&& Logical AND All combinations of types Integer 1 && 1 = 1 1 && !"" = 1

1 && 0 = 0 1 && "cat" = 1

|| Logical OR All combinations of types Integer 1 || 1 = 1 0 || 0 = 0

1 || 0 = 1 "" || !"cat" = 0

Bitwise Logical Operators

~ Bitwise

complement

& Bitwise AND Integer-integer Integer 0b11111110 & 0b01010101 = 0b01010100

^ Bitwise exclusive ORInteger-integer Integer 0b11111110 ^ 0b01010101 = 0b10101011

| Bitwise inclusive ORInteger-integer Integer 0b11111110 | 0b01010101 = 0b11111111

Integer-integer Integer ~0b11111110 = 0b00000001

Shift Operators

<< Left shift Integer-integer Integer 0b11111110 << 3 = 0b11110000

>> Right shift Integer-integer Integer 0b11111110 >> 1 = 0b01111111

Table 4.2 Operators (Continued)

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Chapter 4: Operators File-based Decoding User Manual

Operator Symbol Description Operand Types

Result Types Examples

Assignment Operators

= Assignment Any Any A = 1

+= Addition

assignment

-= Subtraction assignment

*= Multiplication

assignment

/= Division

assignment

%= Modulus

assignment

>>= Right shift

assignment

<<= Left shift

assignment

&= Bitwise AND

assignment

^= Bitwise exclusive

OR assignment

|= Bitwise inclusive

OR assignment

Integer-integer Integer x = 1

String-str ing Strin g a = "one "

Raw byte-raw byte Raw z = '001122'

List-list List x = [1, 2]

Integer-list List y = 1

Integer-string Strin g a = "number = "

String-lis t List s = "one"

Integer-integer Integer y = 3

Integer-integer Integer x = 3

Integer-integer Integer s = 3

Integer-integer Integer y = 3

Integer-integer Integer b = 0b11111110

Integer-integer Integer a = 0b11111110

Integer-integer Integer e = 0b11111110

Integer-integer Integer i = 0b11111110

B = C = A

x += 1 = 2

a += "two" = "one two"

z += '334455' = '001122334455'

x += [3, 4] = [1, 2, 3, 4]

y += [2, 3] = [1, 2, 3]

a += 2 = "number = 2"

*Note: integer-string concatenation uses decimal conversion.

s + ["two"] = ["one", "two"]

y –= 1 = 2

x *= 1 = 3

s /= 1 = 3

y %= 1 = 0

b >>= 1 = 0b01111111

a <<= 3 = 0b11111110000

a &= 0b01010101 = 0b01010100

e ^= 0b01010101 = 0b10101011

i |= 0b01010101 = 0b11111111

Table 4.2 Operators (Continued)

14 LeCroy Corporation

File-based Decoding User Manual Chapter 4: Operators

Operator Symbol Description Operand Types

Result Types Examples

List Operators

sizeof() Number of

elements

head() Head List Any head([1, 2, 3]) = 1

tail() Ta i l List List tail([1, 2, 3]) = [2, 3]

first() Returns the first

element of the list and resets the list iterator to the beginning of the list

next() Returns the next

element of the list relative to the previous position of the list iterator

more() Returns a non-zero

value if the list iterator did not reach the bounds of the list

last() Returns the last

element of the list and resets the position of the list iterator to the end of the list

prev() Returns the

previous element in the list relative to the previous position of the list iterator

Any Integer sizeof([1, 2, 3]) = 3

sizeof('0011223344') = 5 sizeof("string") = 6 sizeof(12) = 1 sizeof([1, [2, 3]]) = 2

*Note: the last example demonstrates that the sizeof() operator returns the shallow count of a complex list.

*Note: the Head of a list is the first item in the list.

*Note: the Tail of a list includes everything except the Head.

List Any list = [1, 2, 3];

for( item = first(list); more(list); item = next(list) ) { ProcessItem( item ); }

List Any list = [1, 2, 3];

for( item = first(list); more(list); item = next(list) ) { ProcessItem( item ); }

List Integer list = [1, 2, 3];

for( item = first(list); more(list); item = next(list) ) { ProcessItem( item ); }

List Any list = [1, 2, 3];

for( item = last(list); more(list); item = prev(list) ) { ProcessItem( item ); }

List Any list = [1, 2, 3];

for( item = last(list); more(list); item = prev(list) ) { ProcessItem( item ); }

Table 4.2 Operators (Continued)

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File-based Decoding User Manual Chapter 5: Comments

Chapter 5: Comments

Comments may be inserted into scripts as a way of documenting what the script does and how it does it. Comments are useful as a way to help others understand how a particular script works. Additionally, comments can be used as an aid in structuring the program.

Most comments in CSL begin with a hash mark (#) and finish at the end of the line. The end of the line is indicated by pressing the Return or Enter key. Anything contained inside the comment delimiters is ignored by the compiler. Thus,

# x = 2;

is not considered part of the program. CSL supports only end-of-line comments of this type (comments that can be used only at the end of a line or on their own line). It's not possible to place a comment in the middle of a line using the hash mark.

Writing a multi-line comment requires either beginning each line with the hash mark (and ending that line with a Return or Enter) or using a comment block.

A comment block begins with "/*" and end with "*/". Everything inside of the comment block is ignored.

Example of a multi-line comment with comment delimiters on each line:

# otherwise the compiler would try to interpret # anything outside of the delimiters # as part of the code.

Example of a multi-line comment block:

/* The compiler ignores all contents of the block comment. */

The most common use of comments is to explain the purpose of the code immediately following the comment. For example:

# Add a profile if we got a server channel if(rfChannel != "Failure") {

result = SDPAddProfileServiceRecord(rfChannel, "ObjectPush"); }



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File-based Decoding User Manual Chapter 6: Keywords

Chapter 6: Keywords

Keywords are reserved words that have special meanings within the language. They cannot be used as names for variables, constants or functions.

In addition to the operators, the followin

Keyword Usage

select select expression

set Define a global variable

const Define a constant

return return statement

while while statement

for for statement

if if statement

else if-else statement

default select expression

null Null value

in Input context

out Output context

g are keywords in CSL:

Table 6.1 Keywords

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