DAP Technology 1394, Operation Manual

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Recorder
79 Copyright © DapTechnology B.V., 2005-2019 - All Rights Reserved., 5/20/2019
At the top of the view you see a toolbar with some buttons and controls like zoom in and zoom out
buttons, the cursor time indicator and buttons to quickly find other packets of the same type as the current
selected one or packets with errors. Below the toolbar is the time line. It is a horizontal black line with the
packets and events drawn on top of it.
Clicking with the mouse above the base line, will select the first packet or event that can be found to the
right of the clicked position. The selected packet or event will automatically be selected in all other
Recorder views.
The time at the cursor position is displayed in the toolbar. It can display the absolute time or a relative
time. In absolute time mode, time 0 is defined as the trigger time or if no trigger detected, the time of the
very first packet or event. In relative mode the displayed cursor time is relative to a reference time. This
reference time is indicated in the Time View as a vertical dotted line (see above). The reference time is
set when switching from absolute to relative mode, in which case the reference time will be set to the
cursor time. Additional mouse clicks will move the cursor, but not the reference. This makes time
measurements very easy. To measure the time between the start of a request packet and the start of its
response packet for instance, select the request packet, switch to relative mode and select the response
packet. The time between them will be displayed in the toolbar. Note that the selection of the packets can
also be done in one of the other views of the Recorder.
To measure packet lengths, prefix length etc., you can click with the mouse below the base line. This will
move the cursor to that position, without searching the first packet to the right of it.
7.2.2. Details
The Time View displays all packets and events on a time line with a resolution of about 20 nS
(1/(2*24.576 MHz)) to be exact) for a FireSpy400 and about 10 nS (1/(4*24.576 MHz)) for a FireSpy800
and newer.
It has a toolbar of its own and a part where the packets and events are displayed.
7.2.2.1. Toolbar
The Toolbar has the following indicators and buttons:
Zoom in
With this button you can zoom in. You will see more details of the packets.
Zoom out
With this button you can zoom out. You will see fewer details of the packets.
Time of display width
This box indicates the time that corresponds to the displayed time in the time view. In the example above
this is 1.03 mS, or about 8 isochronous cycles.
An alternative way to zoom in and out is to select a value for this box from the popup list. The total zoom
range is about 1:8000000.
Toggle between absolute and relative time
With this button you can toggle between absolute (default) and relative cursor mode. When not pressed,
the cursor is in absolute mode; the time displayed in the 'Cursor time' box (next toolbar item) is the time of
the cursor position expressed in seconds, after the trigger occurred. If no trigger position defined
(Recorder not triggered) the time is expressed in seconds after the start of the first packet.
As soon as the button is pressed, the 'Cursor time' is relative to the cursor position at the time the button
is pressed. Thus immediately after pressing this button, the 'Cursor time' will be zero (relative to itself).