Rockwell Automation 1771-DA,D17716.5.13 U MNL 1771-DA ASCII I/O MODULE - Manual (Page 247)

ASCII Module
For PLCĆ3 Proessor
Appendix B
B-25
This program allows you to display two messages files on demand
(NO TAG). One message file contains a message variable (timer
accumulated value). When you enter the word GO from the
keyboard of the peripheral device, your program starts a five-second
write block transfer one-shot routine that transfers message files 1
and 2 to the peripheral device.
When the string of data containing GO is transmitted to the ASCII
module’s input buffer, the module sets the new data flag (SW2>0),
and transfers data and the new data flag to the processor data table.
Figure B.12
Example Application Program
O0252
07
B0020
02
MOV
MOVE FROM A TO R
A : WB000:0327
0000000000000000
R : WO000:0200
0000000000000000
RUNG NUMBER RM0
Zero out CW1 on power-up
U
RUNG NUMBER RM1
Power-up initialization rung
O0200
07
RUNG NUMBER RM2
O0252
07
B0020
10
B0020
RUNG NUMBER RM3
TON
TIMER ON
1.0 SECOND
TP =
TA =
T0001
2
0
T0001
17
TE
T0001
15
TD
10
T0001
15
B0020
10
RUNG NUMBER RM4
Initialize for 2 seconds
L
Example Application Read/Write
Program