Siemens Pre-Processor Syntax

This document lists the 840D syntax supported by the pre-processor.

Important: Note that the 840D pre-processor is for the SIEMENS style dialect and will not work properly in ISO dialect. If ISO dialect is used, it is recommended not to use this pre-processor.

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1. Pre-processor setup

2. Operators

3. Arithmetic operators & functions

4. Unconditional branching

5. Conditional branching

6. Repetition

7. Variables

8. Sub-program

9. Other matching patterns

10. Misc Functions

11. System Variables

12. Frame support

1. Pre-processor setup

The 840D pre-processor can be setup in order to be a little bit more flexible. This is done via the macro function $FCEPP( ). This function’s purpose is really to communicate information that are specific to some pre-processor without being standard on every one of them.

These are the configuration parameter supported by the 840D pre-processor.

• $FCEPP('PROCESS', <operation>, <boolean>)

Parameter 1: This function tell the pre-processor which operation it should take care of. The options available here are ‘COMMENTS’, ‘MESSAGES’ and ‘SUBPROGRAMS’

Parameter 2: $TRUE to tell the pre-processor to process the specified operation. $FALSE to tell the pre-processor not to process it (So the user can do it within a macro).

Description: They all default to $TRUE so the pre-processor will handle them if not instructed otherwise.

• $FCEPP('GLOBALDEF', <boolean>)

Parameter: $TRUE or $FALSE

Description: When set to $TRUE, the CNC variables declared from the MCD data or pushed using a macro EXEC command will all be global variables. If $FALSE (default), they will be local to the current source stack from where they are defined.

The standard usage of this function is to turn GLOBAL definition true and then EXEC multiple variable declaration blocks from the program startup macro, then turn the GLOBAL definition back off.

• $FCEPP('PROCESSGUDFILES' [, <seq>])

Parameter: The parameter is optional. Its a sequence of strings representing the GUD file names.

Description: If no values are passed, there is a standard list of GUD files that will be looked for and processed. Those are “SMAC_DEF”, “MMAC_DEF”, “UMAC_DEF”, “SGUD_DEF”, “MGUD_DEF”, “UGUD_DEF”, “GUD4_DEF”, “GUD5_DEF”, “GUD6_DEF”, “GUD7_DEF”, “GUD8_DEF”, “GUD9_DEF”.

• $FCEPP('SETFILEROOT', <folderpath>)

Parameter: Specify the absolute path to the folder to be used as the root of the controller.

Description: The ROOT folder will act as the root from the internal folders of the 840D. This is where the subprograms will be looked for and processed from. The main program should also be there if it contains embedded subprograms.

• $FCEPP('COLLAPSEASSIGNSPACES', <boolean>)

Parameter: $TRUE or $FALSE

Description: When turned $TRUE, this functionality will remove any spaces before and after address assignation so the CE can match them more appropriately. ( Ex: “X = 3.4” will become “X=3.4” ). The default value is $FALSE which is not to collapse the spaces.

• $FCEPP('COLLAPSEASSIGNS', <boolean>)

Parameter: $TRUE or $FALSE

Description: When turned $TRUE, this functionality will remove the assignation character ‘=’ when the address to the left of the assignation is only 1 character long. ( Ex: “X=23.1” will become “X23.1” ). The default value is $FALSE which is not to remove the assignation character.

• $FCEPP('SETALSEVERITY', <severity number>)

Parameter: ICAM Severity number from 0 to 99

Description: Specify the severity to set for all SETAL() 840D functions. By default alarms comes out to the console as diagnostic messages. This function is used to change the severity level so they could be output as warning, error or fatal errors.

• $FCEPP('APPLYFRAMES', <LOGICAL>)

Parameter: LOGICAL value indicating to use the frames

Description: The default is $FALSE in V20 and $TRUE in V21. The reason for this is not to impact existing V20 production CE's.

If $FALSE, the FRAME transformation chained are still parsed, computed and acquired from the simulation but will not automatically be applied back in to the simulation when changed from the program. The user can use macro to access those FRAME system variables via $FCEGNCV(...) which will return them the 12 element matrix of the combined frame.

2. Supported operators

• == Is equal

• <> Not equal

• >= Greater or equal than

• > Greater than

• <= Less or equal than

• < Less than

• B_AND Bitwise AND

• B_OR Bitwise OR

• B_XOR Bitwise exclusive OR

• B_NOT NOT operation

3. Supported arithmetic operators & functions

• • Subtraction

• • Addition

• * Multiplication

• / Division

• = Assignation

• ( ) Priority

• SIN(x) Sinus

• ASIN(x) Arcsinus

• COS(x) Cosinus

• ACOS(x) ArcCosinus

• TAN(x) Tangeant

• ATAN2(x) ArcTangeant

• SQRT(x) Square root

• ABS(x) Absolute value

• ROUND(x) Rounding value

• ROUNDUP(x) Rounding value UP

• TRUNC(x) Truncate the fractional part

• POT(x) Power of 2

• LN(x) Logarithm

• EXP(x) Exponential value

4. Unconditional branching

Syntax	Description
GOTOB label	Jump to a specific label before the current block GOTOB label1
GOTOF label	Jump to a specific label after the current block : GOTOF label1
GOTO label	Jump to a specific label. GOTO label1
GOTOC label	Jump to a specific label. Do not diagnose if label not found. GOTOC label1
GOTOS	Jump to the start of the program/subprogram. GOTOS

5. Conditional branching

Syntax	Description
IF (x) GOTOF label IF (x) GOTOB label	Evaluate boolean condition x and branch if true IF (VAR1==12) GOTOF 30
IF (x) ... ELSE ... ENDIF	Evaluate boolean condition and execute following blocks if true, execute blocks after the ELSE if false. Stop at the ENDIF IF (VAR1==12) ... ELSE ... ENDIF
CASE ...	CASE expression with jump to specific labels. CASE (I) OF 1 GOTOF label1 2 DEFAULT GOTOF label2 label1: G0 X5. label2: G0 X-5.

6. Repetition

Syntax	Example
LOOP ... ENDLOOP	LOOP ... ENDLOOP
FOR var=value TO endvalue ... ENDFOR	FOR i=1 TO 10 ... ENDFOR
WHILE (expression) ... ENDWHILE	WHILE i>1 ... ENDWHILE
REPEAT ... UNTIL (expression)	REPEAT ... UNTIL i==1
REPEAT (label) (repeat_count)	REPEAT LBL1 P=3
REPEAT (label_begin) (label_end) (repeat_count)	REPEAT LBL1 LBL2 P=3
REPEATB (label) (repeat_count)	REPEATB LBL1 P=5

7. Variables

Syntax	Description
DEF <scope><type><name>	Declare a variable. type can be INT, REAL,BOOL,CHAR,STRING,AXIS,FRAME. DEF INT i1 DEF REAL r1=1.4, r2=3.4 DEF STRING[12] str1="Hello" The scope can be NCK or CHAN: NCK: The variable will be global to the whole job. CHAN: The variable will be scoped to current channel only.
R<number> R[<number>] $R<number> $R[<number>]	R variables from R0 to R100 R2=23
AX[<axis var>]	The macro AX[] can be use to get the axis name so the CE can process the right axis DEF AXIS _AXVAR = X AX[AXVAR]=150. This last line will be preprocessed to “X=150.”

8. Sub-program related

Syntax	Description
EXTERN <subprogname and parameters>	Declare a subprogram. The <VAR>in the parameter declaration means that the value will be passed as a reference. You MUST declare the subprogram for the pre-processor to be able to call them. EXTERN Sub1(REAL,INT,INT) EXTERN Sub1(VAR REAL,VAR INT,VAR INT)
L<number>	Predefined calsub command. This would call a subprogram file with the name of the calsub. Meaning a call like L210 would look for a L210.SPF file. These calls CAN’T have parameters. L47
PROC <subprogname and parameters>	Just like EXTERN declar a subprogram. The PROC keyword defined it (this should be the first line of a subprogram). PROC Sub1(REAL length,INT i,INT j)
M17 or RET	The M17 or RET command end the current subprogram or main program. The pre-processor do not support the return to another position using parameters with the RET command.
P<number>	Program execution count. Default is P1 (as in one execution of the subprogram). SUB1(VAR1,I2) P3
CALL <subprogram name>	Calling a subprogram with filename specified. The filename may have to be modified from the subprogram startup macro to match the actual filepath in the PC. CALL “/wkp.dir/sub”
EXTCALL <subprogram name>	Calling a subprogram with filename specified. The filename may have to be modified from the subprogram startup macro to match the actual filepath in the PC. EXTCALL “/wkp.dir/sub”
MCALL <subprogram call>	Having the MCALL on the same line as the subprogram calling will make that call happen on every blocks until the modal call is cancelled. MCALL L70
MCALL	Cancelling a modal subprogram call. MCALL

** The PCALL command is not supported yet.

Rules to follow for the sub-programs to be found

Subprogram files: The root folder for the subprogram need to be set by using the $FCEPP('SETFILEROOT','<absolute path>') macro function, preferably in the program startup macro. This folder will act as the internal root folder.

All the file and folder names under the root one must be in PC format and not internal 840D filename format. This mean that a folder called “_N_DEF_DIR” would need to be called “def.dir” and a subprogram file named “_N_SUBPROG1_SPF” would be called “subprog1.spf”. So basically, the rules are removing the leading “_N_”, having the 3 character extension use a dot instead of an underscore, and the filename being lowercase (case does not really matter in windows though).

Subprogram in current source: When calling a subprogram name, if the subprogram is not found as a file, it will be looked up inside the current source. The rules for this is to look for a rewind line (Start with a %) containing the name of the subprogram.

9. Other matching patterns

Syntax	Description
DEFINE <text>AS <text>	Define macro to replace something by something else in the block DEFINE M5 AS M3
MSG(<text message>)	Operator message MSG(this is a message)
'H<hexadecimal characters>'	Hexadecimal value 'HFF'
'B<binary digits (0 or 1)>'	Binary value 'B0100111'
<name>:	Defining a label so that we can jump to it. LABEL1:
<number>EX-<number>	Exponential notation 23.3EX-4
string1<<string2	String concatenation operator sf=STR1<<STR2
AC(<value>)	Specify axis value as absolute
IC(<value>)	Specify axis value as incremental

10. Misc Functions

Here is the supported conversion utility functions. See the official 840D control manual for description.

• AXSTRING()

• ISAXIS()

• ISNUMBER()

• ISVAR()

• ISFILE()

• NUMBER()

• AXNAME()

• TOUPPER()

• TOLOWER()

• STRLEN()

• INDEX()

• RINDEX()

• MINDEX()

• MATCH()

• SUBSTR()

• SETAL()

• ROUNDUP()

• MINVAL()

• MAXVAL()

• BOUND()

11. System Variables

The set of supported system variables is very limited. Here is what is supported at this time.See the official 840D control manual for description.

• $AA_IW

• $AA_IB

• $AA_IM

• $MN_SCALING_SYSTEM_IS_METRIC

• $MN_SCALING_VALUE_INCH

• $P_AXN1

• $P_AXN2

• $P_AXN3

• $P_BFRAME

• $P_DRYRUN: Always 0 in simulation

• $P_F

• $P_FA

• $P_GG

• $P_IFRAME

• $P_ISTEST

• $P_MC

• $P_MSNUM

• $P_PFRAME

• $P_PROG

• $P_S

• $P_S_TYPE

• $P_SDIR

• $P_SEARCH

• $P_SEARCH1

• $P_SEARCH2

• $P_STACK

• $P_SUBPAR

• $P_UIFRNUM

• $P_UIFR

12. Frame Support

The following transformation can be used to calculate final frames and assign the value to a FRAME variable.

• CTRANS(...)

• CFINE(...)

• CROT(...)

• CSCALE(...)

• CMIRROR(...)

Accessing a FRAME component using the available identifiers TR,FI,RT,SC,MI

Ex: R15 = $P_PFRAME[X,TR]

Note:This is only a subset of the Siemens frame support.