SSR-1U User’s Manual
Rev -, 27 Dec 2019
© 2019 Slerj, LLC
13
www.slerj.com
o
When the file type is
tt
(time tagged), bytes are encapsulated into an archive file
structure that associates a timestamp with each group of received bytes with a
resolution of 2ms. The time tagged archive format overcomes all of the
limitations of the tagged line format, but requires post processing to retrieve the
data. The archive is not intended to be human readable. A utility to perform the
post processing, STTP, is provided with source code. For details, see Section 6
Time Tagged Archives.
File Mode
Supported file creation modes are
retry
,
overwrite
, and
append
. When file mode is
retry
,
the SSR-1U will continue to retry the file creation operation until it succeeds. File
creation can fail if a file with the same name already exists. This mode is a useful
complement to user definable file paths (next bullet).
Overwrite
will cause an existing
file to be replaced by a newly commanded recording.
Append
will cause new data to be
appended to an existing file. For both
overwrite
and
append
modes, if the file specified
by File Path does not exist, it is created.
File Path
The File Path parameter holds a path template that specifies the name and location of the
file to be created when recording is commanded. A path template is a normal path string
that has replaceable fields defined in Table 3 below. A field is identified in the template
by a backslash followed by one of the field identifiers, or several consecutive identifiers
encapsulated in square brackets. For example, the path template /c[chms].dat would be
translated to the path /c1083000.dat for channel 1 if the time is 08:30:00 when a file is
created. Similarly, the path template /gps/nmea\4.txt would be replaced by
/gps/nmeaXXXX.txt where XXXX is a number that is incremented on each attempt to
open the file. Currently, path templates of up to 44 bytes are supported, and the resulting
path (with fields replaced) must be no more than 80 bytes.
Table 3. Path Template Field Codes
Field
Identifier
Replaced With
c
*
channel number [1-3]
Y
year [00-99]
M
month [01-12]
D
day [01-31]
h
hour [00-23]
m
minute [00-59]
s
*
second [00-59]
t
tenth of second [0-9]
y
year (4 digit) [2001-2099]