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Chapter 17: Error Correction, Flow Control, Data Compression
17.1.1 E
RROR
-C
ORRECTION
N
EGOTIATION
B
UFFER
The
\C
command setting determines whether the answering ISDN TA/V
stores received data in its memory buffers during the interval that an error-
correction protocol is being negotiated between the two devices.
\C0
No data is buffered during the error-correction negotiations.
Spurious data which the remote device sends to establish the
link may be passed to the DTE.
\C1
Received data is stored within the ISDN TA/V’s buffers
during the negotiations.
\C2
No buffering of data occurs during the link negotiations,
and the ISDN TA/V switches to buffer mode when an error
correction cancel character is received. This option is best
used if both error-correcting and non-error-correcting
modems frequently call your ISDN TA/V, and you want to
speed up the connection time with non-error-correcting
ISDN TA/Vs by avoiding the error-correction negotiations.
17.1.2 D
EFINING AN
E
RROR
-C
ORRECTION
C
ANCEL
C
HARACTER
This feature is only referenced if the
\C
command is defined as
\C2
. The
error-correction cancel character enables the remote ISDN TA/V user to stop
the error-correction negotiations between the data-communication devivces,
by simply pressing a keyboard key. The ISDN TA/Vs will then connect in non-
error-correcting buffer mode.
The keyboard character that will be recognised by your ISDN TA/V as the
error-correction cancel character is defined by the
%A
command setting,
using the ASCII value of the required character. The default setting is
%A13
;
the numeral 13 being the ASCII value of the carriage-return key.
When comparing incoming characters for a match against the error
correction cancel character, your ISDN TA/V ignores parity and passes the
matching character to the DTE as data.
