Echelon MPR-50 Multi-Port Router - Manual (Page 47)

Using Buffer Recover Mode
You can use the MPR-50 Buffer Management utility’s buffer recovery mode to
recover router nodes that have had invalid buffer configurations programmed into
them. Without the MPR-50 Buffer Management utility, buffer recovery can be
difficult. For example, some configurations result in a router that is only capable of
receiving a few network packets before it enters a state in which it can no longer
receive messages. In these cases, it might be necessary to reset (power cycle) the
router before attempting recovery. As a further complication, the Monitor Node
periodically tries to communicate with these router nodes, which uses packet buffers
if the router node is configured incorrectly.
When you click the Buffer Recover Mode button, the MPR-50 Buffer Management
utility enters the buffer recovery mode; if you click this button again, the utility
returns to buffer configuration mode. While the utility is in buffer recovery mode,
any Service Pin message captured by the utility causes it to perform the following
steps:
1. It checks the Program ID to ensure that the message came from a router.
2. It uses the Neuron ® ID to address a buffer configuration message to the near
router node using the un-ack’d service. The utility uses this service because the
node might not be able to generate a response. The router is also reset as a
result of the buffer configuration message.
3. After a small delay, the utility uses the same Neuron ID to send a buffer
configuration message to the far router node using the un-ack’d service. The
router is reset as a result.
4. After another small delay, the utility reads the router’s far side buffer
configuration and confirms it.
If this process is successful, you should proceed with the next router using the
connectivity that you now have with the recovered router. If it is impossible to
recover the other routers using the internal channel path, you may have to approach
the routers from each of their external channel interfaces.
Note: A single “safe” default buffer configuration is used for all recovery operations
(the same one used for the default configuration of the FT10 nodes). Normally, the
internal node configuration is different from the external node configuration, and the
TP1250 configuration is quite large. To correct for this difference, after the recovery
process is complete, you should re-configure all five routers using the normal buffer
configuration mode.
Fixing the MPR-50 buffers because of a corrupted buffer can take several attempts to
fix all five routers.
To fix the MPR-50 buffer sizes:
1. Decommission all the routers in the MPR-50 if they have been commissioned
before. If the MPR-50 has not been commissioned, proceed to step 2. To
decommission the routers, perform either of the following steps:
a. Use your Integration Tool (for example, the LonMaker tool).
b. Press the Service Pin button on each router for at least 20 seconds until the
Status LED flashes orange.
2. Connect your Network Interface to any of the MPR-50 routers.
MPR-50 Multi-Port Router User's Guide 39