HEIDENHAIN TNC 426 CB, Technical Manual

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7 – 44 HEIDENHAIN Technical Manual TNC 426, TNC 430
MGROUPS.SYS In the system files PLC:\MGROUPS.SYS and PLC:\MSPLIT.SYS, you define
the M functions to be output after a block scan. (See “Returning to the
Contour” on page 6 – 294)
MSPLIT.SYS M functions that are effective in several groups are divided in the MSPLIT.SYS
file into function components. (See “Returning to the Contour” on page 6 –
294)
PLCSOFTK.SYS Path for the file names of the PLC soft-key pictures. (See “PLC Soft Keys” on
page 6 – 273)
CYCLE.SYS Definition of the soft-key structure, if you have integrated OEM cycles. This
file is created automatically by the PC software CycleDesign (see OEMCYC
directory).
NCMACRO.SYS Names of the NC macros
TC = <Name of the tool change macro>
PALLET = <Name of the pallet change macro>
CLAMP = <Name of the NC macro for changing the fixture (FIX)>
RUNCANCEL = <Name of the macro called when an NC program is
cancelled>
RESETINIT = <Name of the macro called when
traverse reference point
is
left>
STARTUPCANCEL = <Name of the macro called when mid-program startup is
not finished with
restore machine status >
Example entry: TC=PLC:\NC_MACRO\TOOLCALL.H
In order to increase the speed with which NC macros are executed, limit-
switch monitoring can be turned off with FN17: SYSWRITE ID230 NR5. At the
end of an NC macro the limit switch monitoring is always switched on.
As of NC software 280 476-03:
PGM CALL
, including NC macros, and
CYCL CALL
(for cycles greater than 68) are
calculated automatically with the look-ahead function and run without exact
stop. At the beginning and end of the called program or cycle, it can happen
that a missing synchronization between machine status and look-ahead
calculation may lead to problems.
Example:
A
TOOL CALL is run in look-ahead calculation. In this TOOL CALL a PLC function
is needed (e.g. opening the tool changer gate). The tool is automatically
changed on the machine. During this time the look-ahead calculation reaches
another
TOOL CALL
. Since the PLC function has been fulfilled (the tool changer
gate is open), the look-ahead calculation is continued. After the first tool
change has been completed, the PLC function is no longer fulfilled (the tool
changer gate is closed). The second
TOOL CALL would be executed if the PLC
function is not fulfilled (the tool changer gate is closed).
The function
FN20: WAIT FOR SYNC provides a remedy for this problem. If this
function is programmed at the beginning of an NC program (NC macro) or
cycle, in the look-ahead calculation the
PGM CALL (NC macro call) or CYCLE CALL
is not executed until the calling program has actually reached the
PGM CALL
(NC
macro call) or CYCL CALL.