Yaskawa MP920 User's Manual Design - Manual (Page 147)

4.3 Position Control
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„ Position Reference
There are two methods of setting the position reference: Direct designation, which directly
sets the position reference in OL††12, and indirect designation, which specifies the number
of the position buffer from which the position reference is stored in OL††12.
There are two direct designation methods: The absolute position reference mode, in which
the absolute position is set in OL††12, and the incremental addition mode, in which the
present travel distance is added to the previous position reference value (previous value of
OL††12).
Table 4.13 shows the parameters relating to the position reference.
* 1. This parameter is invalid when the position reference value selection is
the position buffer (indirect designation).
* 2. The setting data differs according to the setting of the Position Refer-
ence Value Selection (bit 12 of OW††01) and the Position Reference
Type (bit 14 of OW††01).
When indirect designation is used to specify the position buffer number, the positions stored in the posi-
tion buffer are treated as absolute positions.
When a motion command (OW††20) is not used, the position reference value set in OL††12 is
treated as an absolute position.
Table 4.13 Position Reference Parameters
Parameter Type Parameter No.
(Register No.)
Name Description Initial Value
Motion Setting
Parameters Bit 12 of
OW††01 Position Refer-
ence Value
Selection Sets the position reference designation method.
• 0: Direct designation
Directly sets the position data in OL††12.
Specifies in bit 14 of OW††01 whether the posi-
tion data is to be set in the absolute position mode
or the incremental addition mode.
• 1: Indirect designation
Sets the number of the position buffer in
OL††12. The absolute position must first be
stored in the specified position buffer.
0
Bit 14 of
OW††01 Position Refer-
ence Type Specifies the type of position data.
• 0: Absolute position mode
Sets the absolute position in OL††12.
• 1: Incremental addition mode
Adds the present travel distance value to the previ-
ous value of OL††12 and sets the result in
OL††12.
*1
1
OL††12 Position Refer-
ence Setting
Sets the position data. *2 0
IMPORTANT