HEIDENHAIN TNC 410 - Manual (Page 47)

34 4 Programming: Fundamentals of NC, File Management, Programming Aids
4.3 Creating and Writing Programs
Organization of an NC program in HEIDENHAIN
conversational format
A part program consist of a series of program blocks. The figure at
right illustrates the elements of a block.
The TNC numbers the blocks in ascending sequence.
The first block of a program is identified by “BEGIN PGM,” the
program name and the active unit of measure.
The subsequent blocks contain information on:
■ The blank form
■ Tool definitions and tool calls,
■ Feed rates and spindle speeds as well as
■ Path contours, cycles and other functions.
The last block of a program is identified by “END PGM,” the pro-
gram name and the active unit of measure.
Defining the blank form — BLK FORM
Immediately after initiating a new program, you define a cuboid
workpiece blank. This definition is needed for the TNC’s graphic
simulation feature. The sides of the workpiece blank lie parallel to
the X, Y and Z axes and can be up to 30 000 mm long. The blank
form is defined by two of its corner points:
■ MIN point: the smallest X, Y and Z coordinates of the blank form,
entered as absolute values.
■ MAX point: the largest X, Y and Z coordinates of the blank form,
entered as absolute or incremental values.
The TNC can display the graphic only if the short side of the BLK
FORM is longer than 1/64 of the long side.
4.3 Cr
eating and
W
riting Pr
ogr
ams
Y
X
Z
MAX
MIN
Block:
10 L X+10 Y+5 R0 F100 M3
Path function Words
Block number