LXE 1280, Справочное руководство

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Sending Forms to a Host 139
E-SW-LDSPLUSRG-G LDS Plus Reference Guide
Sending Forms to a Host
An inbound form is a form that the DOS terminal sends to the host computer.
When a DOS terminal sends a form to the host computer, it sends the form message header (first
three protected characters of the form) along with all of the unprotected characters.
The first two characters of the inbound form identify it to the host computer. The third character
of an inbound form is always a right square bracket (instead of a right parenthesis on a non-form
message).
Inbound forms with unprotected data fields can be sent to the host with or without serial numbers,
and either compressed or uncompressed.
Control Characters Used for Inbound Forms
The control character for an inbound form identifies the message as a form to the host computer,
and it indicates whether a sequence number is included.
There are two possible control characters for inbound forms – left apostrophe ( ‘ ) or the lower
case letter a:
‘ (60 hex)
Indicates that it is a form message without sequence numbers. For example:
<E3M‘7B]
where
<E3 is a message from terminal E3.
‘ identifies a form message without sequence numbers.
7B is the form number, as assigned by the host computer or contained in a
stored form, and barcode entry was activated by the form.
a Indicates that it is a form message with sequence numbers. For example:
<E3M a 57B]
where
<E3 is a message from terminal E3.
a identifies a form message with sequence number 5.
7B is the form number, as assigned by the host computer or contained in a
stored form, and barcode entry was activated by the form.