Rockwell Automation 2706-DXX Dataliner Message Display DL5 Series - Manual (Page 45)

2706-UM001A-US-P
Run Mode 5-3
Description of Run Mode In the run mode, the DL5 waits for the host to send message triggers and/or
variable data. The DL5 receives message triggers and variable data through
either the parallel or serial port. The serial and parallel ports cannot be
active at the same time. The Serial Trigger/Configure DIP switch
determines the active port (Serial Trigger position = serial port, Configure
position = parallel port). When a message trigger is received, the DL5
searches its memory for the selected message, inserts any imbedded
variables, and then displays the message.
If another message trigger is sent to the DL5 before the first message’s wait
time has expired, the DL5 stores the message trigger in a message buffer.
The capacity of the message buffer is one message. Refer to the following
example which shows how the message buffer operates.
1. The host controller sends a message trigger for message number 27 to
the DL5. The DL5 removes the message trigger from the message buffer
and displays message number 27.
2. While the DL5 is displaying message number 27, the DL5 receives a
message trigger for message number 18. The message trigger is stored
in the message buffer.
3. The DL5 receives an additional message trigger for message number 45,
while message number 27 is still displayed. Since the message buffer
already contains a message trigger, the trigger for message number 45 is
ignored.
DL5
Message Buffer Message #27
is displayed
27
Control System
Message Trigger
#27 Sent
DL5
Message Buffer
Message #27
is still displayed; its wait
time has not expired.
18
Control System
Message Trigger
#18 Sent
DL5
Message Buffer Message #27
is displayed
Control System
Message #45 Ignored
Buffer is Full
18
Message Trigger
#45 Sent