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7
DESCRIPTIONDESIG.DATE
01 00.07.05 First issue.
21i/210i-MA OPERATOR'S MANUAL
Replacement of “15.7 PROCESSING MACRO
STATEMENTS” explanation
B-63094EN/02-1
3 Details
The explanation of “II programming, 15.7 Processing macro statements” is replaced as follows.
15.7 PROCESSING MACRO STATEMENTS
For smooth machining, the CNC prereads the NC statement to be performed
next. This operation is referred to as buffering. During AI advanced preview
control mode, the CNC prereads not only the next block but also the multiple
blocks. And in the cutter compensation mode (G41, G42), the CNC prereads
the NC statements two or three blocks ahead to find intersections even if the
CNC is not in AI advanced preview control mode. Macro statements for
arithmetic expressions and conditional branches are processed as soon as
they are read into the buffer. Therefore, the timing of the macro statement
execution is not always the specified order.
At the blocks containing M00, M01, M02 or M30, blocks containing M-codes
for which buffering is suppressed by setting parameter (No.3411-3432), and
blocks containing prevention buffering G codes such as G53, the CNC stops
to preread the NC statement after that. Then, the stop of the macro statement
execution is guaranteed until such M codes or G codes complete its
execution.
15.7.1 Details of NC statements and macro statements execution
> N1 G31 X100.0 ;
N2 #100=1
:
> : Block being executed
NC statement execution
Macro statement execution
Buffer
N1
N2
When the next block is not
buffered (M codes that are
not buffered, G53, G31, etc.)
Note
In case that you need to execute the macro
statement after completing the block just before
the macro statement, specify M code or G code
that are not buffered just before the macro
statement. Specially, in case of reading /
writing the system variables to control signals,
coordinates, offset value, etc., it may different
system variable data by the timing of the NC
statement execution. To avoid this phenomenon,
specify such M codes or G codes before the macro
statement, if necessary.