Siemens SINUMERIK 840D sl Programming Manual page 434

Data description
9.2 Cycle data
M0 for tolerance alarms "oversize", "undersize", or "permissible dimensional difference exceeded"
_CBIT[2]=0:
_CBIT[2]=1:
Central marker for basic dimension system of the control
_CBIT[3]=0:
_CBIT[3]=1:
When starting up the measuring cycles, this bit has to be set according to the basic settings
of the PLC MD 10240: SCALING_SYSTEM_IS_METRIC must be set.
If modifying the basic settings of the control results in _CBIT[3] no longer matching MD
10240, arrays _TP[], _WP[], _KB[] and _EV[] will be converted the first time a measuring
cycle is called after the modification and a message will be output.
The data for tool measurement with rotating spindle (_CM[ ], _MFS[ ]) are also converted as
are the data in the _SPEED[ ] field.
Tool measurement and calibration in the WCS in CYCLE982
_CBIT[5]=0:
_CBIT[5]=1:
Note
From measuring cycles SW 6.3, function switchover via _MVAR is available. A separate tool
probe array is used there, the _TPW[ ] field, for calibration/measurement in the WCS.
Logging without output of the measuring cycle name and measuring variant
_CBIT[6]=0:
_CBIT[6]=1:
9-24
When the alarms "oversize", "undersize", or "permissible dimensional difference
exceeded" occur, no M0 is generated.
M0 is generated when these alarms occur.
Basic system is based on inches
The basic system is metric
The tool is measured and the tool measuring probe is calibrated in the machine
coordinate system.
The tool probe data are stored in the _TP[ ] field.
The tool can be measured and the tool probe calibrated in the active WCS. In
this case, when calibrating and measuring, the same prerequisites must exist
regarding the actual WCS. This means that tools with active transformation can
also be measured, e.g. TRAANG.
Notice: When calibrating and measuring, the _TP[ ] field is also used here.
When logging, the measuring cycle name and the measuring variant are written
into the log.
When logging, the measuring cycle name and the measuring variant are not
output into the log.
Programming Manual, Release 04/2006, 6FC5398-4BP10-0BA0
Measuring cycles