LXE 1280 Reference Guide
164
Expanded Functions
LDS Plus Reference Guide
E-SW-LDSPLUSRG-G
L: Set the RcvSeqNumbers Parameter to Yes
Expanded Function L is a message that enables the DOS terminal to use host-generated
sequence numbers. Sequence numbers prevent the DOS terminal from acting upon duplicate
messages from the host computer.
sequence numbers. Sequence numbers prevent the DOS terminal from acting upon duplicate
messages from the host computer.
Rule: Use any combination of numeric and/or alphabetic (uppercase or
lowercase) characters for the sequence numbers. LXE recommends that
the host application use the sequence numbers 1 through 7 for regular
messages, excluding broadcast messages.
the host application use the sequence numbers 1 through 7 for regular
messages, excluding broadcast messages.
Rule: Do not send a sequence number with this message. Presumably, you are
sending this message to turn on the RcvSeqNumbers parameter in the
DOS terminal so that the DOS terminal will accept sequence numbers.
Any subsequent messages that you send must contain a sequence
number.
DOS terminal so that the DOS terminal will accept sequence numbers.
Any subsequent messages that you send must contain a sequence
number.
What Happens
Expanded Function L sets the LDS Plus RcvSeqNumbers parameter in the DOS terminal to yes.
When you set the RcvSeqNumbers parameter to yes, the DOS terminal expects sequence numbers
from the host computer. The DOS terminal interprets the first text character of a message from the
host as a sequence number and compares it to the first text character of the previous message.
When you set the RcvSeqNumbers parameter to yes, the DOS terminal expects sequence numbers
from the host computer. The DOS terminal interprets the first text character of a message from the
host as a sequence number and compares it to the first text character of the previous message.
If these characters are the same, the DOS terminal acknowledges the message but does not display
it. If the sequence number is different from the previous message, the DOS terminal acknowledges
the message and then acts upon it.
it. If the sequence number is different from the previous message, the DOS terminal acknowledges
the message and then acts upon it.
See “Sequence Numbers (SEQ #)” in Chapter 4, “Messages”, for more information.
Attributes
No beeps
No change in automatic transmit buffer length
No change in automatic transmit buffer length
Example
Y
is the control character used when sending
an expanded function.
L
is the N/EF character that sets the
RcvSeqNumbers parameter to yes.
<02S
Y
L
C
R
L
F
Figure 5-14 Expanded Function L Forced Message
See Also
Expanded Function M: “Set RcvSeqNumbers Parameter to No.”