Generating CL Records in a Macro

There are several ways that macros can issue CL records. The TAPEWT macro command (described in a later section) is one way. This section will describe other ways.

Post-Processor Commands in a Macro

All post-processor records can be specified within macros. If an alias does not exist for the record then the record can be issued using an explicit string. (e.g., #2000:9999). Macro expressions (local variables, keywords, etcetera) can be used to describe each record argument. REAL, STRING, MINOR, RECORD or SEQUENCE expressions can be given. Each SEQUENCE argument causes the sequence to be inserted at that position. NULL and LOGICAL arguments are not allowed. Consider the following SPINDL macro:

MACRO SDL
$$ Match any SPINDL record that specifies RANGE,HIGH SPINDL/$P1*,RANGE,HIGH,$P2* PPRINT/'Selecting MEDIUM range' SPINDL/$P1,RANGE,MEDIUM,$P2

CLDATA input	Matches
SPINDL/RANGE,HIGH,CLW,500,SFM	$P1=<> $P2=<CLW,500,SFM>
Macro output
PPRINT/'Selecting MEDIUM range' SPINDL/RANGE,MEDIUM,CLW,500,SFM

CLDATA input	Matches
SPINDL/100,RANGE,HIGH	$P1=<100> $P2=<>
Macro output
PPRINT/'Selecting MEDIUM range' SPINDL/100,RANGE,MEDIUM

By default, records generated in this way are candidates for macro matching. In this way, a macro may “call” another macro. Macros that are already being executed are not candidates for invocation. This means that a macro can never call itself, either directly or indirectly. Macro matching may be disabled to prevent command records in a macro from calling macros. The “Macro Invocation” section describes the MATCH/OFF command that does this.

Suppressing Post-Processor Commands

As mentioned earlier, it is possible to ignore a particular type of record entirely by creating a user-defined macro that consists only of a syntax definition line describing the syntax to be suppressed. For example, the following macro suppresses all CAMERA commands.

CAMERA/
TERMAC

Outputting the Matched Record (OUTPUT)

The OUTPUT command is used to instruct GENER to process the matched CL file command exactly as it was read. Any modification made to any $Pn variables or any minor words will be ignored when this command is used.

Macro SDL
SPINDL/$P1,[$P2(CLW,CCLW)],[RANGE,$P3] PPRINT/'Code put here will precede the SPINDL command' OUTPUT PPRINT/'Code put here will follow the SPINDL command'

CLDATA input	Matches
SPINDL/100,CLW,RANGE,4	$P1=100 $P2=CLW $P3=4
Macro output
PPRINT/'Code put here will precede the SPINDL command' SPINDL/100,CLW,RANGE,4 PPRINT/'Code put here will follow the SPINDL command',

CLDATA input	Matches
SPINDL/500,RANGE,4,CCLW	$P1=500 $P2=CCLW $P3=4
Macro output
PPRINT/'Code put here will precede the SPINDL command' SPINDL/500,RANGE,4,CCLW PPRINT/'Code put here will follow the SPINDL command'

Generating Other CL Record Types

Any class record can be issued from within a macro. This can be done by specifying the explicit representation of the record. For instance, “#5000:5/2,2,2” specifies a 5000 class record, subclass 5 with three arguments. For those familiar with ISO class definitions you will recognize this as a GOTO record. Common records have built in aliases. They are described in the following sections. With these commands, only REAL and MINOR arguments may be specified, depending on the record type. NULL, LOGICAL, STRING and SEQUENCE arguments are not permitted.

Motion CL Records

Motion statements (class 5000 records) are used to cause the tool to move from its current location to a new one and/or to modify the orientation of the tool axis with respect to the machined part. All motions are point to point since no other canonical form exists in post-processor macros. For example, it is not possible to generate a set of moves to follow an arbitrary surface since no mechanism exists to define such surfaces. However, the different formats of motion statements are sufficiently powerful to handle a wide scope of applications.

At this point, a distinction must be made between CL file and machine coordinates. Post-processing a “CL file point” (defined by an XYZ triplet) results in a “machine point” that is, most of the time, very different than the originating CL file point. Many factors determine the mapping between CL file and machine points but for the purpose of the example, consider the following NC statements:

UNITS/INCHES
GOTO/1,1,1

Clearly, the CL file point value corresponding to the above program would be XYZ (CL file) = 1,1,1. Now if the machine units is in millimeters, the resulting machine point would be XYZ (machine) = 25.4,25.4,25.4. Therefore, confusion would arise in a post-processor macro as to what point a motion statement refers to: the CL file or the machine point! When TRANSL is specified the coordinates will be translated into machine coordinates.

There are three motion commands supported in post-processor macros namely:

GOTO

FROM

GODLTA

The GOTO and GODLTA statements both cause motions to occur but the FROM statement changes the post-processors reference point. It is mostly used when dealing with incremental machines. The following lists and describes all the motion statements that can be used in post-processor macros.

In all formats below, xm,ym,zm refer to machine coordinates and xc,yc,zc refer to CL file coordinates. The i,j,k triplet represents the orientation vector that the tool should assume at the end of the motion. However, it must be understood that the above triplets really stand for arbitrary arithmetic expressions. For example, format #1 below could be coded as “GOTO/$XC–3,$YC,$ZC– %G00+1”.

This command will generate a circular motion record. The xc,yc,zc parameters define a point on the axis of the circle. The xv,yv,zv parameters define a vector parallel to the circle axis and the direction of rotation about the circle using the right hand rule. The radius parameter specifies the radius of the circular surfaces being machined. The optional count modifier is used when you need to generate circular motions in excess of 360 degrees. A count of 1 will generate an arc from the current position to the next position specified by xe,ye,ze. A count of 2 will generate an arc exactly 360 degrees larger than the default.

The MOVARC command must be followed by a GOTO/ command that defines the end point of the arc. The coordinates of the GOTO command can be in machine or CL file coordinates. The keyword TRANSL is used to specify that the coordinates are in CL file coordinates. The MOVARC coordinates are presumed to be in the same coordinate system as the end point GOTO coordinates.

Move to the machine point xm,ym,zm.

Move to the CL file point xc,yc,zc.

Move to the CL file point xc,yc,zc with a tool vector orientation of i,j,k.

Change the reference point to xm,ym,zm.

Change the reference point after conversion of xc,yc,zc to machine coordinates.

Change the reference point after conversion of xc,yc,zc to machine coordinates and conversion of i,j,k to machine angles.

Move the machine tool tip to a new location that is “delta” machine units along the current tool axis.

Move the machine tool tip location by an increment of xm,ym,zm.

Move the machine tool tip to a new location that is “delta” CL file units along the current tool axis.

Move the CL file tool tip location by an increment of xc,yc,zc.

Move the machine tool tip to a new location that is “delta” CL file units along the current tool axis with a tool orientation vector of i,j,k.

Move the CL file tool tip location by an increment of xc,yc,zc; the tool orientation vector is set to i,j,k.

Implied MULTAX

In all the above formats that modify the tool orientation vector, MULTAX is automatically generated by the post-processor only for that next motion, if the multi-axis mode was not already on.

For example, the following post-processor motion statement (format #3 above):

GOTO/TRANSL,1,2,3,1,0,0

is conceptually equivalent to the following portion of an NC program:

MULTAX/ON
TLAXIS/1,0,0
GOTO/1,2,3
MULTAX/OFF

Note that when using the TRANSL method, the specified coordinates and optional vector are subject to all the processing normally performed on CL coordinates. This includes effects of the ORIGIN/ , TRANS/, tool offsets, etcetera.

Examples of motion statements:

GOTO/1,1,1

Go to the machine point 1,1,1.

GOTO/TRANSL,1,1,1

Go to the CL file point 1,1,1.

GOTO/TRANSL,1,2,3,0,0,1

Go to the CL file point 1,2,3 with the tool axis parallel to the Z axis.

GODLTA/TRANSL,2

Slide the tool tip 2 CL file units along the current tool axis.

Environment Control CL Records

The following 6000 class commands are supported and have predefined aliases: INTOL, OUTTOL and CUTTER. All require a single numeric argument. The following 9000 class commands are supported: MULTAX and UNITS. MULTAX requires a single minor word argument (ON or OFF). UNITS requires at most two arguments. The first is a minor word (CM, INCHES, MM, or FEET). The second, if present, is a numeric value specifying a scale factor. The 14000 class record (FINI) is also supported. It does not require any arguments.

Other class CL commands must be specified using explicit strings (#15000:0) for the command name. Arguments can be specified in the standard manner. Such records can also be constructed using the “CLPUT” macro command and put out using the “TAPEWT” macro command. Refer to the “CL File I/O From Macros” section.