MITSUBISHI ELECTRIC Mitsubishi Programmable Logic Controller QD75D - Manual (Page 316)

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MELSEC-Q
9 MAJOR POSITIONING CONTROL
9.1.4 Confirming the current value
Values showing the current value
The following two types of addresses are used as values to show the position in
the QD75.
These addresses ("current feed value" and "machine feed value") are stored in the
monitor data area, and used in monitoring the current value display, etc.
Current feed value
•
This is the value stored in " Md.20 Current feed value".
•
This value has an address established with a "machine OPR" as a
reference, but the address can be changed by changing the current
value to a new value.
•
This value is updated every 1.8ms.
Machine feed value
•
This is the value stored in " Md.21 Machine feed value".
•
This value always has an address established with a "machine OPR"
as a reference. The address cannot be changed, even if the current
value is changed to a new value.
•
This value is updated every 56.8ms.
The "current feed value" and "machine feed value" are used in monitoring the
current value display, etc.
0 1 to Md. 20 Current feed value
t
V
OP
20000
Current value changed to
20000 with current value
changing instruction
0 1 to Md. 21 Machine feed value
Address after the current
value is changed is stored
10000
10000
Address does not change even
after the current value is changed
Fig. 9.8 Current feed value and machine feed value