Cmd_set_gating, Cmd_set_gating_time_window_width – GBS Elektronik MCA-527 Firmware Commands User Manual
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MCA527
Command name
CMD_SET_GATING
Compatibility
New MCA527 command.
Execution right
Necessary
Description
The command sets the parameter (mode, signal and shift) for gating.
mode:
0 = none
1 = discard
2 = sort by state
3 = sort by time
rejection signal:
0 = low
1 = high
shift:
0 … 255 * 100 nsec (only relevant for mode 'sort by state')
The command is ignored and responds with an error value if a measurement is still running or if
there is any conflict with other settings (see remarks).
Format
integer
integer
char
char
char
char
integer
integer
Parameter
preamble
command
mode signal shift
0
0
end flag
Byte string (HEX)
A5
5A
0F
01
mode signal shift
00
00
00
B9
9B
Remarks
According to the signal on the gate input the counts are sorted or discarded.
In discard mode, the counts are just discarded.
In 'sort by state' mode, the counts are sorted according to the current signal state either into the
useful spectrum or into the so-called rejected spectrum. This rejected spectrum is usable for
stabilization. This mode is intended for LED stabilized detectors that deliver a signal while the LED is
on.
In 'sort by time' mode, each (either rising or falling) signal edge restarts a timer. According to the time
elapsed since the timer has been started, the counts are sorted into eight different spectra which
refer to eight time windows whose width can be adjusted with the command
CMD_SET_GATING_TIME_WINDOW_WIDTH. Counts which occurs between the measurement
start and the first relevant signal edge as well as counts which do not apply to any time window are
discarded. This gating mode is in conflict with the MCS mode (see CMD_SET_MODE) and with the
stabilization using the rejected spectrum (see CMD_SET_STABILISATION).
Command name
CMD_SET_GATING_TIME_WINDOW_WIDTH
Compatibility
New MCA527 command (since firmware version 14.02).
Execution right
Necessary
Description
The command sets the width of the time windows for the gating mode 'sort by time' (see
CMD_SET_GATING).
index:
0 … 7
width:
1 … 4294966289 * 100 nsec
0xFFFFFFFF = infinite (until the next gating signal)
The command is ignored and responds with an error value if a measurement is still running.
Format
integer
integer
integer
long
integer
Parameter
preamble
command
index
width
end flag
Byte string (HEX)
A5
5A
32
01
index
l
index
h
width
l
...
...
width
h
B9
9B
19 Since firmware version 14.02.
16