Unihedron SQM-LU-DL, Руководство оператора

Страница: 65 / 101

8.2 Response details
8.2 Response details
8.2.1 Reading request
The “Reading” request “
rx
” or “
Rx
” commands the SQM-LU-DL to provide the current darkness value as well as all
variables used to generate that result.
Readings produced by this request are averaged internally by using the last 8 readings and shifting those values through
an 8 cell buffer then summing and dividing by 8. Use the “ux” command to get the un-averaged and most recent value.
Averaging is only performed on period-mode readings (when the light sensor frequency is below 128Hz). Frequency mode
readings (above 128Hz) are automatically averaged because the reading is taken from a one second sampling of pulses.
The format of the response is shown in table 8.3:
Table 8.3: Reading request response
Column Example value Description
0
r
Indicates that a reading is being returned.
2-8
06.70m
Reading in
mag
arcsec
2
.
Leading space for positive value.
Leading negative sign (-) for negative value.
A reading of
0.00m
means that the light at the sensor has reached
the upper brightness limit of the unit.
10-21
0000022921Hz
Frequency of sensor in Hz.
23-33
0000000020c
Period of sensor in counts. Counts occur at a rate of 460.8 kHz
(14.7456MHz/32).
35-46
0000000.000s
Period of sensor in seconds with millisecond resolution. Determined
by dividing the above counts value by 460800.
48-54
039.4C
Temperature measured at light sensor in degrees C.
Leading space for positive value.
Leading negative sign (-) for negative value.
55-56 Carriage return (0x0d), Line feed (0x0a).
An example of the response is:
r, 06.70m,0000022921Hz,0000000020c,0000000.000s, 039.4C
0123456789 123456789 123456789 123456789 123456789 123456
Future versions of this reading string will only modify reported values beyond position 54. Characters 0 to 54 may be
considered stable.
A special case “
Rx
” command returns the serial number in the same format as the interval report does. See page 86
“Setting Interval reporting parameters” for report details.
8.2.2 Unaveraged reading request
The “unaveraged reading” request “u
x
” commands the meter to provide the current darkness value as well as all variables
used to generate that result. This readings is not averaged out like the “rx” command.
The format of the response is shown in table 8.4:
Unihedron SQM-LU-DL Operator’s Manual -
20220119
65