Figure 5, Openldv programmer’s guide 59 – Echelon OpenLDV User Manual

Page 67

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OpenLDV Programmer’s Guide

59

Extended Header

Extended Data Type

Extended Data Version

Extended Data

BF

Packet Size

Flags

Extended Header Size

Absolute Timestamp

In Seconds

Absolute Timestamp

In Milliseconds

Differential Timestamp

In Microseconds

SICB

Timestamps

Header

SICB

Extension

Command

Length N

Data[0]

Data[1]

Data[N-1]

Data

Payload

NI Header

Queue

Command

Buffer Structure for

Commands That Do Not Use

a Message Queue

Buffer Structure for

Commands That Use

a Message Queue

Length N

Data[0]

Data[1]

Data[N-1]

Data

Payload

NI Header

LdvEx Buffer

Format

SICB Buffer

Formats

Figure 5. Application Buffer High-Level Structure

For commands that use a message queue, the queue bits in the SICB buffer

indicate the path by which an incoming message was received, or by which an

outgoing message should leave the network interface. For example, an outgoing

message can use the standard, non-priority, output queue or the priority output

queue. Likewise, an incoming message might be received as a response to a

pending request, or it might be a normal incoming message. See Network

Interface Commands on page 77 for a description of the queue and command-code

values.
The OpenLDV Developer Example contains relevant data type definitions,

constants, and enumerations for messaging using the SICB buffer. The complete

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