Licht
http://www.licht-labs.com
Rev. A2 (23–01–09)
MFC-200/P Technical Manual
12
Parameter
:
Backoff Delay (Fixed)
Options
: 1 to 100 ms.
Description
: See description for
Backoff Delay (Random)
.
Parameter
:
Backoff Delay (Random)
Options
: 1 to 100 ms.
Description
: The MFC-200/P is designed for multi-drop scenarios where more than
one outstation may transmit over the same line. To handle collision avoidance, a backoff
scheme is implemented. Before transmitting, the MFC-200/P always waits for the line to
become idle. Once that happens, it waits for
T
delay
=
T
f ixed
+
T
random
ms, where
T
f ixed
is the fixed backoff delay and
T
random
is a random value, uniformly distributed between 0
and the random backoff delay parameter. If after
T
delay
ms the line is still idle, then the
MFC-200/P begins transmission.
Parameter
:
Insert Inter-frame Gap
Options
: Never, Always.
Description
: The DNP3 specification states that no inter-frame gaps are required. How-
ever, some masters have been observed to drop frames when no inter-frame gaps are pro-
vided. This option allows communicating with such non-compliant devices. We discourage
its use, given that the forced inter-frame gap implies a forced backoff-delay.