USING THE NON-INTELLIGENT TERMINAL PROTOCOL
UNILINK HOST ADAPTER A-8
USER MANUAL
A.2.1 Err
ors and Err
or Recovery
The following ERROR RESPONSE codes from Chapter 6 relate to NITP data
link
errors:
0086 HOST FRAME TOO LONG — the frame exceeded 590 bytes in total
length. Remember that the message body is composed of two ASCII
characters for each hexadecimal message byte. This means that your
message
data can not be longer than 290 bytes which
yields 580 ASCII
character
bytes.
0087 HOST
FRAME TOO SHORT — the frame received was less than twelve
bytes in length. The message body must at least consist of a command
code. The frame then must be a minimum of twelve characters for the
delimiters,
character count, command code message body
, and ECC.
0089 MISSED START OF MESSAGE DELIMITER — the semicolon that
begins
a NITP frame was missing. Correct the frame and
retransmit it.
008B MESSAGE LENGTH COUNT ERROR — the character count field
value did not match the number of characters received. This could be
caused
by a noise spike that deletes one or
more characters, or an error
in
the software driver
. In either case, your applications software should
retry the message at least three times. If this same error returns all
three
times, check for an error in your software driver
.
008C MESSAGE CHECKSUM BAD — the checksum calculated by the
adapter did not match the ECC field value. Retry the
message at least
three
times. If this same error returns all three times, check for an error
in
your software driver
.
008D INVALID HEX-ASCII CHARACTER RECEIVED — one of the ASCII
characters
between the beginning and ending delimiters was not in the
NITP
character set. This could be caused by noise spikes that change
bit
values. Retry the message at least three times. If this same error
returns
all three times, check for an error in your software driver
.