Fagor CNC 8060 - Page 222

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Installation manual
CNC 8060
CNC 8065
3.
INTRODUCTION TO THE PLC.
(REF: 1402)
PLC program execution.
3.3 PLC program execution.
Main module (PRG)
The main module is processed as follows:
1 The PLC assigns the current value of the physical inputs (remote modules) to the I
resources.
2 The PLC assumes the current values of the internal CNC variables (CNCREADY, START,
FHOUT, .....).
3 The PLC executes the main program (PRG).
4 The PLC updates the internal CNC variables (EMERGEN, STOP, FEEDHOL, ...) with the
current values of the associated PLC resources.
5 The PLC assigns the current value of the PLC's "O" resources to the physical outputs
(remote modules).
6 The PLC concludes the cycle and is ready for the next scan.
Periodic module (PE)
The periodic module is processed as follows:
1 The PLC takes into account the current values of the physical inputs (remote modules)
at the beginning of the module.
2 The PLC executes the periodic module.
3 The PLC assigns the current value of the PLC's "O" resources to the physical outputs
(remote modules).
4 The PLC concludes the execution of the periodic Module.