Envoy ACP/XF Configuration and Management Manual

WAN Subsystem Profiles and Modifiers for
EnvoyACP/XF
EnvoyACP/XF Configuration and Management Manual—429232-003
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Optional Modifier Descriptions
3. Some remote stations are disconnected.
4. The local station enters LDS.
RNRTIMER is supported only through the WAN subsystem. There is no SETMODE
function to allow an application to modify the RNRTIMER value dynamically.
RS422/RS232
SECONDARY
See PRIMARY/SECONDARY.
SENDRNRRETRY/NOSENDRNRRETRY
The NOSENDRNRRETRY modifier applies only to a station sending RNRs (receiver
not ready). The default value for this modifier is SENDRNRRETRY.
The RNR state typically is caused by the following conditions:
•
A local station automatically enters RNR state when it can no longer accept frames
from the remote station because the local station’s buffers are already full. For
example, a local RNR state is likely to occur if the station has received numerous
I-frames from the remote station and the local application has not posted timely
READ requests to clear these frames from the buffer. The RNR state, which is
caused by buffer depletion, is cleared after the application has issued a READ to
retrieve the I-frames from the buffer, thereby releasing some buffer space.
Note. When this timer expires, a primary station sends a DISC. A secondary station sends a
DM to any received frame that is not a mode-setting command.
Default: RS232
Units: N/A
Range: N/A
Alternate
Modifier:
RS422
Default: SENDRNRRETRY
Units: N/A
Range: N/A
See
also:
RECVRNRRETRY/NORECVRNRRETRY
Note. The buffer-depletion problem should not occur if the application program is
presenting READ requests in a timely manner. In general, the application program should
always have at least one READ pending at all times. When any READ completes, another
READ should immediately be issued.