Omega Engineering OMB-CHARTSCAN 1400, Руководство пользователя

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Configuration Aspects for Programmers Appendix B
B-22 ChartScan User’s Manual
7 - End Scan Pointer This field represents the location in the current trigger block that the end scan occurred.
This pointer will always be relative to the trigger point. Since the end scan must always occur after the trigger
event this pointer will always be greater than 0. If the end scan has not yet occurred at the time of the U6 query,
this field will have the value of -0999999. This field will always be the same as the Stop Scan Pointer unless a
post-stop count is specified (
Y
command) in which case the End Scan Pointer will be greater than the Stop Event
Pointer by the value of the post-stop count.
8 - Block Status This field represents the status of the current trigger block. If the current trigger block is still
being acquired, the value of this field will be 00. If the current trigger block has been completely acquired and
has terminated normally the value will be 01. If, however, the current trigger block has pre-maturely terminated
(because of user intervention) the value will be 02.
Trigger blocks are not assigned a trigger block number per se. Trigger block numbers are relative to the read
and write blocks respectively. The current trigger block always refers to the trigger block that is currently being
read. For example, the current read trigger block is always trigger block 1. Conversely, the current write trigger
block is always the value of Blocks Available in the Buffer Status String. With this in mind, look at the
following example a of Buffer Status String response.
The following table describes the fields for the
U6
response when the acquisition buffer is empty. For ease of
reference the previous figure has been repeated.
Example of Buffer String when the Acquisition Buffer is Empty
Field Response Implication
1 0000000 No trigger blocks available.
2 0000000 No scans are available.
3 -0999999 The current read pointer is undefined.
4 00:00:00.000,
00/00/00
The trigger time stamp is undefined.
5 -0999999 The stop event pointer is undefined.
6 00:00:00.000,
00/00/00
The stop event time is undefined.
7 -0999999 The end scan pointer is undefined.
8 00 The current trigger block is not complete.