Siemens SINUMERIK 840D sl Function Manual page 6

Preface
Quantity structure
Explanations concerning the NC/PLC interface are based on the absolute maximum number
of sequential components:
● Mode groups (DB11)
● Channels (DB21, etc.)
● Axes/spindles (DB31, etc.)
Data types
The control provides the following data types that can be used for programming in part
programs:
Type Meaning
INT Signed integers
REAL Numbers with decimal point
BOOL Boolean values
CHAR ASCII characters and bytes
STRING Character string, null-terminated
AXIS Axis names
FRAME Geometrical parameters for moving, rotating, scaling, and
mirroring
Note
Arrays can only be formed from similar elementary data types. Up to 3-dimensional arrays are possible.
Querying REAL variables
We recommend that querying REAL or DOUBLE variables in NC programs and synchronized
actions is programmed as limit value evaluation.
Example: Querying the actual value of an axis for a specific value
DEF REAL AXPOS = 123.456
IF ($VA_IM[<axis>] - 1ex-6) <= AXPOS <= ($VA_IM[<axis>] + 1ex-6) ; actual position
ELSE
ENDIF
6
...
...
Value range
-2.147.483.648 ... +2.147.483.647
≈ ±5,0*10 ... ≈ ±1,7*10
-324
TRUE (≠0) , FALSE (0)
0 ... 255 or -128 ... 127
Maximum of 400 characters + /0
(no special characters)
All axis names available in the control
system
---
== AXPOS
<> AXPOS
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
+308
Basic Functions