LXE 1280, Reference Manual

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Expanded Functions 157
E-SW-LDSPLUSRG-G LDS Plus Reference Guide
H: Clear the Compose Buffer to Header
Expanded Function H is a message that clears the compose buffer and leaves the message header
intact.
Rule: You must include two characters of text with Expanded Function H.
What Happens
When the DOS terminal receives an Expanded Function H message, it takes the two characters of
text from the receive buffer and moves them into the first two positions of the compose buffer and
automatically inserts a right parenthesis character “)” into the third position of the compose buffer.
The remainder of the compose buffer is blank; therefore, the DOS terminal removes any previous
data in the compose buffer.
If this function does not have two characters of text the compose buffer header consists of 01.
Application
An Expanded Function H message causes the DOS terminal to simulate the action of an operator
pressing a function key to perform different DOS terminal actions.
You can use Expanded Function H to remove a form from the compose buffer.
Function Key Setup
You must set up the host computer application program to associate each function key assignment
in the DOS terminal to a process you want to use.
The valid two characters of text associated with a function key are 1 through 40 (for function keys
1 through 40). The DOS terminal moves these characters into the first two positions followed by
right parenthesis character ) that the DOS terminal automatically places in the third position of the
compose buffer.
For example, the DOS terminal displays
11)
for function key F11. If function keys 1 through 9
are used, an ASCII space (or blank) appears before a single digit number.
For example, the DOS terminal displays
9)
for function key F9 with a space before the nine.
Attributes
Two beeps
No change in automatic transmit buffer length