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Rtr-10 message buffers and transaction records – Echelon LonWorks Router User Manual

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outgoing buffer queue. Thus, priority processing of these outgoing messages is

assured because the transmitting side will send messages from the priority output

buffer queue before sending messages from the non-priority output buffer queue.

Figure 8 shows the message flow through the input and output buffer queues. This

message flow is duplicated for messages moving in the opposite direction, that is,

another set of input and output buffer queues exist for messages flowing in the

opposite direction.

1

2

1

2

1

2

3

N - 1

N

Message Receiving Side

Message Sending Side

Input Buffer Queue

Priority Output Buffer Queue

Normal Output Buffer Queue

Direction of Message Flow

Figure 8. Buffering Scheme for a L

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Router

The size and count of the message buffers is limited by the amount of RAM on

the router.

RTR-10 Message Buffers and Transaction Records

There are three different versions of the router firmware for the RTR-10 router.

To determine the router firmware version of your router, see Appendix B,

Determining RTR-10 Firmware Version.
Some versions of the RTR-10 routers were shipped with a reduced buffer and

transaction record capacity. This does not impact system performance. However, a

catastrophic failure of the router can occur if the buffers or transaction records on a

router with reduced buffer and transaction record capacity are reconfigured and

assume that a larger buffer and transaction record space is available. This could

occur if you are using a manufacturing test station to reconfigure routers based on

the higher router buffer and transaction record capacity. It can also occur if you

use a network installation tool that reconfigures router buffers or transaction

records when replacing a router using a non-standard configuration. The failure

condition that occurs is that the router will go into the application-less state and

will no longer function as a router. This failure mode cannot be recovered in the

field. If you are making the change with a tool based on the OpenLNS Server or

the OpenLNS Commissioning Tool (or LNS and the LonMaker Turbo Integration

Tool), in some cases, the tool will prevent an invalid configuration; however, in

other cases the tool may allow an invalid configuration and the router will fail. Use

the tables, below, to understand the correct buffer and transaction record

configurations for your RTR-10 router.

Depending on your firmware, buffers and transaction records are allocated

according to the following tables. For versions A and C, Table 3 shows the

transaction record configurations for receive and transmit transactions, and the

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Router User’s Guide

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