DAP Technology 1394, Operation Manual

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Symbol Recorder
140 Copyright © DapTechnology B.V., 2005-2019 - All Rights Reserved., 5/20/2019
(For details about training please refer to 13.3.2.1 of the IEEE1394-2008 specification)
TRAINING/OPERATION symbols are used to synchronize bits/character and the scrambler. When a node
is ready (in sync) it starts sending OPERATION symbols.
After both ports receive OPERATION symbols, they are synchronized and can start testing for a possible
loop. described in chapter 14.7 of the IEEE1394 Specification.
Loop Test Symbol (LTS)
The picture above show something that looks like an invalid packet, but are in fact the transmission of
Loop Test Symbols. It starts with a SPEEDb control followed by a number of DATA_PREFIX symbols.
Please refer to 14.7.2 of the IEEE1394-2008 Specification for more info on the format of the symbol.
Port Becomes Active
After the port detects making it active will not result in a loop, it sends an ATTACH_REQUEST which is
responded with a BUS_RESET control. (See Chapter 14.7.9 and 14.7.10 of the specification).
After the Bus reset, each node enters their "Tree identification state machine" (see chapter 16.4.6).
Directly followed by the Self-identification state machine (see chapter 16.4.7).