ETTC'2003 - SEE

Message Parameter
ID
1 WORD
The END field
The message parameter is often used to carry frame data on ARINC429, RS232/422/485, CAN or
AFDX buses.
The general description is given hereafter :
a) ID field identifies the parameter in one IENA packet. The ID field is mandatory and unique in all
programming version of test installation.
b) LENGTH specifies the size of data parameter in byte excluding padding byte. This is a mandatory
field.
c) Delay field gives the time difference between IENA packet creation and acquired data.
d) DATA field is dedicated to carry either an acquired or internal parameter. It’s a mandatory field.
All data are right justified . A padding byte is added at the end of this field when the length isn’t
16 bits aligned.
It’s a mandatory field. The default value given by the data base is 0XDEAD.
IENA PACKET rules
Parameter rules
- Acquisition equipments could produce in one packet synchronous parameters with several sampling
frequency.
- The more often we found in the same packet only analog parameters with the same sample
frequency. This method optimize the decoding processing time.
- The standard analog parameter packets don’t carry delay and identifier.
- The analog parameters have always the same position in the packet.
- An identifier is only in one packet.
Key Rules
LENGTH
1 WORD
DELAY
Opt, 1 WORD
Byte
1
Byte
2
IENA MESSAGE PARAMETER
DATA MESSAGE
Byte
3
Padding
1 BYTE
The standard parameters carried in a same key shall have the same size and the same structure.
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