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User Threshold ($UT):
$UT -> 300 106 2500[CR] {This command queries or sets the user threshold for the chosen energy scale in units of 1
in 10,000 of the chosen full scale energy. For example setting the value to 300 will set the User Threshold for the
sensor to 3% (= 300/10000) of the chosen energy scale. If the chosen energy scale is 200mJ the threshold will be set
to 3% of 200mJ or 6mJ. Each energy scale has its own value for user threshold so different scales can be set to
different user threshold values}
Examples:
$UT [CR], or $UT 0 [CR] -> *300 106 2500[CR] - Query using no parameter or 0 parameter
$UT 500[CR] -> *[CR] - set new user threshold to 5% of full scale of present chosen energy scale.
Note:
To save new setting as startup default, use $HC S command.
Continuous Send Modes for Pyroelectrics/PD-C Sensors:
In addition to the usual command/reply format described above, a special “Continuous Send” (CS) mode is provided
for Pyroelectric/PD-C sensors to enable data collection at much higher data rates. Several CS modes are provided in
addition to those described above for thermopile/photodiode sensors. The different modes provide several options
of increased data rates but at the expense of increased complexity - the user can choose which mode is most
suitable for their particular application. The CS mode is supported only using a Telnet connection.
Each of these Continuous Send modes is initiated by sending the "$CS x" command and is terminated by sending the
"$CS 1" command, or by sending any other command.
NOTE:
CS Modes 2, 3, 4 for Pyroelectric/PD-C sensors require minimum firmware version 1.12 (use $VE command to
query firmware version) included in PC Application from version 1.11 and above.
1. ASCII MODE $CS 2 (max data rate ~14kHz):
Using this mode, energy data is returned in a simple ASCII format with 4 significant digits. Data is terminated with
the Line Feed/Carriage Return characters, in a similar way to responses from a regular command.
Once per second, frequency data averaged over the last second is provided with the additional key word “FREQ”.
Using this mode there is no way to know for each individual measurement when exactly this pulse arrived or
whether there were pulses missing between each data point recorded.
The maximum data rate (to measure every pulse on the sensor) is ~14kHz using this mode.
Example:
For every pulse measured: *1.234E-1[CR][LF]
{energy is 123.4mJ}
Once per second: *1.234E-1 FREQ 4.321E2[CR][LF]
{energy is 123.4mJ, frequency over last second is 432.1Hz}
2. ASCII MODE $CS 3 (max data rate ~9kHz):
This mode is similar to ASCII mode $CS 2 but with the addition of a pulse index and timestamp for every energy pulse
measurement. The pulse index is a running count of the energy pulses measured. If the pulse rate is lower than the
max data rate, the index will increment by 1 for every pulse measured. If the pulse rate is higher than the max data
rate for every pulse, the index will increment by more than 1 to indicate how many pulses were missed between
each data point. The timestamp records the exact time each pulse was measured with 1 microsecond resolution.
The values of timestamp and pulse index will each increase up to a maximum of 4.29 billion (to be exact,
4,294,967,295 =2^32 - 1) and then cycle back around to zero.
Frequency is not provided in this mode, the user can calculate frequency using the timestamp and pulse index.
The maximum data rate (to measure every pulse on the sensor) is ~9kHz for the first few seconds; it may be slightly
slower after measuring for long periods as the timestamp and pulse index values become longer (= more bytes to
deliver for each data point).
Example:
For every pulse measured: *2222 33333 1.234E-1[CR][LF]
