Rockwell Automation 1772-LS_LSP,D17726.8.6 PROG/OPER MANUAL-MINI PLC-2/05 - Manual (Page 198)

Report Generation
Chapter 17
17-4
The upper byte of word 027 is used to control messages 1-6. Bit 027/10 is
the request bit for message number 1 and so on. Bit 027/16, the busy bit is
set when any of messages 1-6 are requested and remains set until all
requested messages have been printed. Once all messages are printed, bit
027/17 will stay on for 300 milliseconds and is then reset.
Additional Messages
The upper byte of each message control word contains the request bits for
eight messages. There is an easy way to determine the message number
from the bit which requests it. The three right-most digits in the bit
address are coded to the message number. For example, if message
number 312 is of interest, bit 12 of the third message control word requests
message 312 on a false-to-true transition (Figure 17.3).
Figure 17.3
Bit AddressĆMessage Number Relationship
0
1
2
3
4
5
6
7
201 010-017
110-117
210-217
310-317
410-417
510-517
610-617
710-717
202
203
204
205
206
207
210
Control Word Control Word Message
Numbers Address Number
10218
The control word addresses are user selected.
Message number 3XX has a message request bit at address 204/XX. Message request bit
204/XX, when enabled, will activate message number 3XX where XX are bit numbers
00Ć17
8
.
Unlike messages 1-6 which share a common done bit (027-17), the
additional 64 messages each have a separate done bit. After a particular
message is printed, the done bit is set until the user program resets the
request bit. Done bits are located in the lower byte of the message control
words. Figure 17.4 shows this relationship. For example, if 404/15 is the
request bit for a message, the done bit is located at 404/05, one byte below
the request bit.