DAP Technology 1394, Руководство по эксплуатации

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Recorder
93 Copyright © DapTechnology B.V., 2005-2019 - All Rights Reserved., 5/20/2019
The size column displays the total packet size expressed in bytes. If the packet size is not a whole
number of bytes, which is an error condition, the number of whole bytes is displayed plus the '+' sign.
Thus a packet of 27 bits has a size of '3+'. The exact number of bits can be found in the details area,
using the 'Layout' page.
source - destination - label - retry - response-code
The next 5 columns hold information of important packet fields. They are only filled with information for
packets that actually include the corresponding field.
The source and destination have a special format. They are split into bus number and node number. If the
bus number is 1023 (local bus), only the node number will be displayed. Otherwise the bus number and
local number are displayed separated by the ':' character.
For stream packets, the destination column will display the channel number of the stream packet. Channel
31 is displayed as 'ch 31'.
ack
If a packet has a corresponding acknowledge packet, the acknowledge type is displayed in the last
column.
speed
This column indicates the packet speed. Please notice that even though a physical connection at
800Mbit/s is established, it is still possible to send out packets with an effective data rate of 100Mbit/s.
destination offset
In case of Asynchronous Transaction requests this column indicates the memory address offset in the
target node.
data quadlet
In case of an Asynchronous write request or read response this column shows the data quadlet embedded
in the packet header.
time
This column shows the time stamp of the packet/event. By right-clicking on an item in this column it is
possible to change the time reference (time equals zero point) from the first packet/event to the selected
packet/event.
format
This column displays the packet format. This can be legacy, beta or unspecified.
direction
This column indicates if a packet was received or transmitted by the local node. In case of a FireStealth
device, this column indicates whether the packet transferred from port A to port B or the other way round.
UTC
In case a time source like an IRIG board was used for packet time stamping, this column shows the time
stamp in UTC format. Please look at the relevant Settings documentation to set this up.
7.4.2.3. Packet Details
If a packet is selected, the complete line in the packet table is highlighted. If the ‘Toggle packet-details
on/off’ button is pressed (on), the details of the selected packet can be seen right of the list (as in the
example above). This part includes:
Packet Type
In this box the type of packet that is selected can be seen. If the packet type is unknown (e.g. a packet
with erroneous header) this box will say 'unknown packet'.
Show As Packet
This box has a popup list from which you can select a packet type. The packet will be displayed in the
format of the packet type selected here. Initially, it will be the same as the 'Packet Type' box. For
unknown packets, it will be 'unformatted'. This feature can be used to find out for an erroneous packet
what packet it most likely is ment to be, and also to display a packet in its unformatted hexadecimal
quadlet form.