Siemens SIMATIC FM 453, Manual

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10-15
FM 453 Servo Drive / Step Drive Positioning Module
C79000-G7076-C453-01
10.2 Program Execution and Direction of Machining
As a rule, programs are processed by ascending block number.
If programs are processed in reverse, the effects of commands must be taken
into account in the programming:
S
Commands are self-maintaining (G90, G91, G60, G64, G30...G39)
S
Active tool offset (G43, G44, D0...D20)
S
Change of coordinate systems via G87, G88, G89.
For these reasons, a distinction can be made between forward processing and
reverse processing, in terms of both geometry and block transition response.
10.3 Block Transitions
This chapter describes the influence of certain commands on block transi-
tions.
G60 mode is overlaid with G50 and G88 to G89 (force block change on-the-
fly).
The program advances to the next block when the target range is reached.
The influence of M functions is as indicated in machine data item MD32.
Case 1
V
N
i
N
i+1
ÉÉ
ÉÉ
ÉÉ
ÉÉ
ÉÉ
ÉÉ
M
t
É
É
É
t
Forward
Processing
Reverse
Processing
Overview
Exact Positioning -
G60
Output of
M Function Before
Positioning
Writing Traversing Programs