
197
Notification of the Operating Status to the PC
Section 5-5
S
Screen switch strobe flag (bit 12)
When the screen displayed on the NT20S is switched by a designation from the
PC or by the standalone function, the screen switch strobe flag comes ON (1).
On notification to the PC, it returns to the OFF (0) status.
For details on how the screen switch strobe flag is used, see “Notifying the Dis-
play Screen to the PC” (page 160).
S
Numeral setting strobe flag (bit 11)
When numerical data is input to a numeral memory table using the NT20S nu-
meral setting function, the numeral setting strobe flag comes ON (1). On notifi-
cation to the PC, it returns to the OFF (0) status.
For details on how the numeral setting strobe flag is used, see “Notification of
Numbers to the PC” (page 188).
5-5-2
Reading the NT20S Operating Statuses
This section explains how to determine the status of the NT20S, and ascertain its
operating status.
To ascertain the operating status of the NT20S, “PT status” is used.
The NT20S automatically notifies information such as the operating status to the
PT status word of the PT status notify area (PT
→
PC) allocated to the PC memory
as shown below.
Notification of operation mode:
PT operating status
Notification of screen switching:
Screen switch strobe flag
Notification of numerical data upgrade:
Numeral setting strobe flag
S
Restrictions on allocating words
The PT status notify area (PT
→
PC) can be allocated to the PC memory areas
listed in the following table.
Symbol
C Series PCs
Allocated
CVM1/CV Series PCs
Allocated
DM
Data Memory
f
Data Memory
f
CH
Internal/Special Relay
f
Internal/Special Relay
f
TIM
Timer
Timer
CNT
Counter
Counter
HR
Holding Relay
f
–
AR
Auxiliary Relay
f
Auxiliary Relay
LR
Link Relay
f
–
f
: OK
: NG
Since all the CVM1/CV-series special auxiliary relays are allocated to the system,
they cannot be used for applications not related to the system.
The range of each memory area differs according to the PC type. See “Appendix L
PC Memory Map” (page 278 of the APPENDIX L) for more details.
Procedure
1. Use the support tool to allocate the PT status notify area (PT
→
PC) to the PC
memory.
2. Write a PC program to read the “PT status” word of the PT status notify area
and check each bit status.
Summary of Contents for NT20S
Page 1: ...Cat No V020 E1 04 NT20S Programmable Terminal OPERATION MANUAL ...
Page 2: ...i ...
Page 3: ...ii ...
Page 4: ...iii NT series Programmable Terminal Operation Manual Revised August 1997 ...
Page 5: ...iv ...
Page 7: ...vi ...
Page 11: ...x ...
Page 19: ...xviii ...
Page 129: ...110 ...
Page 169: ...150 ...
Page 253: ...234 ...