Omron NT20S Operation Manual page 177

Overview of Direct Connection Operations
Procedure 1. Use the support tool to allocate the PT status control area (PC to PT) to the PC
158
S Available allocation words
The PT status control area (PC to PT) can be allocated to the following PC
areas.
Symbol C Series PCs
DM Data Memory
CH Internal/Special Relay
TIM Timer
CNT Counter
HR Holding Relay
AR Auxiliary Relay
LR Link Relay
Since the special auxiliary relays of the CVM1/CV series PCs are allocated to the
system, they cannot be used for purposes other than the system use. The range
of respective area varies with the type of PC. Refer to Appendix L PC Memory Map
(page 278).
memory.
2. Create a PC program to write the number of the displayed screen to the
"screen switch setting word" in the PT status control area.
Use a 4-digit BCD (binary-coded decimal) value to set a screen number.
If a screen has been switched by operating the PT status control area (PC to PT),
the contents of the "currently displayed screen word" in the PT status notify area
(PT to PC) also change.
S Screen switching timing
The NT20S screen switches when the contents of the "screen switch setting"
have changed. To re-specify the number of the currently specified screen, first
write the value 0000 to clear the screen before writing the appropriate screen
number.
S Use of the screen switching strobe
Create a program to read the number of the currently displayed screen and to
write the number to the "screen switch setting word" at the leading edge of the
"screen switching strobe" of the PT status notify area. This program enables
screen switching by using the touch switches on the NT20S and eliminates re-
peated setting of the same screen number. If the screen switching is not execut-
ed on the NT20S, the screen switching strobe does not need to be checked.
For the screen switching strobe, refer to the "notifying the displayed screen to
the PC" mentioned below.
Allocated CVM1/CV Series PCs
f
Data Memory
f
Internal/Special Relay
Timer
Counter
f
–
f
Auxiliary Relay
f
–
Section 5-1
Allocated
f
f
f: OK
: NG