HEIDENHAIN TNC 426 CB, Technical Manual

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9 – 6 HEIDENHAIN Technical Manual TNC 426, TNC 430
Global and local Q
parameters The values of the global Q parameters can be entered or edited both in the
calling part program as well as in the called OEM cycle. During value transfer
from the calling program to the called program, the value of the global
parameter is not changed.
Editing a local parameter in an OEM cycle does not affect the part program.
Local Q parameters keep their values only in the current program. When an
OEM cycle is called, all values of the local Q parameters are buffer stored and
retain their old values after returning from the OEM cycle.
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Q200 to Q299 are global Q parameters.
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Q0 to Q59 are local Q parameters.
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Q60 to Q99 are either local or global. Use MP7251 to define the effect.
MP7251 Defining Q parameters Q60 to Q99
Input: 0 = Q60 to Q99 local
1 to 40 = Q(100 – <input value>) to Q99 global
Parameters Q0 to Q59 are used in the HEIDENHAIN standard cycles for
mathematical operations. We recommend this for your OEM cycles as well.
Optional
parameters CycleDesign lets you define optional parameters. Use a parameter as optional
parameter if you expand an existing OEM cycle by one parameter.
The advantage is that if existing programs are loaded in which the old cycle
(without the new parameters) is programmed, the new optional parameter is
automatically inserted and preassigned with the default value.
If you were not to define the new parameter as optional, the cycle block could
not be interpreted, and an ERROR block would be inserted.
Warning
The default value for the optional parameter must allow the TNC to run the
old OEM cycle without error!