Notification of the Operating Status to the PLC (Determining the NT20 Operating Status)
5-5-2
Reading the NT20 Operating Status
Symbol
C-series
None
IR Area
H
HR Area
A
AR Area
L
LR Area
T
TC Area
Timer PVs
TU
---
C
TC Area
Counter PVs
CU
---
W
---
TK
---
D
DM Area
E
EM Area
(See note 2.)
E0_to EC_
---
• Screen Switch Strobe Flag (Bit 12)
When the screen displayed on the NT20 is switched by a designation from
the PLC or by the standalone function, the screen switch strobe flag comes
ON (1). On notification to the PLC, it returns to the OFF (0) status.
For details on how the screen switch strobe flag is used, refer to 5-1-5 No-
tifying the PLC of the Display Screen (to Display the Number of Currently
Displayed Screen) on page 174.
• Numeral Setting Strobe Flag (Bit 11)
When numerical data is input to a numeral memory table entry using the
NT20 numeral setting function, the numeral setting strobe flag comes ON
(1). On notification to the PLC, it returns to the OFF (0) status.
For details on how the numeral setting strobe flag is used, refer to 5-3-6
Notification of Numbers to the PLC page 199.
This section explains how to determine the status of the NT20, and ascertain
its operating status.
To ascertain the operating status of the NT20, "PT status" is used.
The NT20 automatically notifies the PLC of information such as the operating
status in the PT status word of the PT status notify area (PT → PLC) allocated
in PLC memory as shown below.
Notification of operation mode:
Notification of screen switching:
Notification of numerical data upgrade:
• Restrictions on Allocating Words
The PT status notify area (PT → PLC) can be allocated to the PLC memory
areas listed in the following table.
Alloca-
CVM1/CV -series
tion
❍
CIO Area
❍
---
❍
AR Area
❍
---
×
TC Area
Timer PVs
---
---
×
TC Area
Counter PVs
---
---
---
---
---
---
❍
DM Area
❍
EM Area
Current bank
---
---
PT operating status
Screen switch strobe flag
Numeral setting strobe flag
Alloca-
CS/CJ-series
tion
❍
CIO Area
---
HR Area
×
AR Area
---
LR Area (See note 1.)
×
TC Area
Timer PVs
---
TC area,
Timer Completion Flags
×
TC Area
Counter PVs
---
TC area,
Counter Completion Flags
---
WR
---
Task Flags
❍
DM Area
Not for
EM Area
Host Link
Current bank
---
EM Area
EM bank 0 to C
Section 5-5
Alloca-
tion
❍
Not for
Host Link
❍
Not for
Host Link
×
×
×
×
Not for
Host Link
×
❍
Not for
Host Link
Not for
Host Link
❍: OK × : NG
209