Trigger Modes - Spectrum digitizerNETBOX DN2.44 Series Hardware Manual

Trigger Modes

Activated Used
Channels Mode
Min
1 Ch Standard Boxcar
FIFO Boxcar 0 (∞)
2 Ch Standard Boxcar
FIFO Boxcar 0 (∞)
4 Ch Standard Boxcar
FIFO Boxcar 0 (∞)
All figures listed here are given in samples. An entry of [8k - 16] means [8 kSamples - 16] = 8176 samples.
Trigger Modes
When using Boxcar Averaging all of the cards trigger modes can be used including software trigger. For detailed information on the available
trigger modes, please take a look at the relating chapter earlier in this manual.
Output Data Format
When using Boxcar Averaging mode the resulting samples will be 32bit signed integer values per channel, that each consist of the sum of a
chosen number of successive RAW samples.
So the resulting „resolution" of the samples increases with the number of averages. For example averaging 16 bit RAW samples two times
results in a final resolution of 17 bit, averaging it four times results in a sample with 18 bit „resolution".
By not dividing down the samples by the number of averages in the firmware and providing the user application with the 32 bit wide sums,
one can take full advantage of the enhanced resolution by using proper data formats in the application software.
Data organization
Data is organized in a multiplexed way in the transfer buffer the same way as the RAW samples would be. If using 2 channels data of first
activated channel comes first, then data of second channel:
Activated Channels Ch0 Ch1
1 channel X
1 channel X
1 channel
1 channel
2 channels X X
2 channels X
2 channels X
2 channels X
2 channels X
2 channels
4 channels X X
The samples are re-named for better readability. A0 is sample 0 of channel 0, B4 is sample 4 of channel 1, and so on. The averaged samples
now just have a wider format of 32 bit independent of the original RAW sample resolution.
144
Loops Number ofAverages
SPC_LOOPS SPC_AVERAGES
Max Step Min Max
not used 2 256
4G - 1 1
not used 2 256
4G - 1 1
not used 2 256
4G - 1 1
Ch2 Ch3 32bit wide averaged samples ordering in buffer memory starting with data offset zero
A0 A1 A2
B0 B1 B2
X C0 C1 C2
X D0 D1 D2
A0 B0 A1
X A0 C0 A1
X A0 D0 A1
X B0 C0 B1
X B0 D0 B1
X X C0 D0 C1
X X A0 B0 C0
digitizerNETBOX DN2.44x Manual / DN6.44x Manual
Step
1
1
1
A3 A4 A5 A6 A7
B3 B4 B5 B6 B7
C3 C4 C5 C6 C7
D3 D4 D5 D6 D7
B1 A2 B2 A3 B3
C1 A2 C2 A3 C3
D1 A2 D2 A3 D3
C1 B2 C2 B3 C3
D1 B2 D2 B3 D3
D1 C2 D2 C3 D3
D0 A1 B1 C1 D1
Mode Boxcar Average (High-Resolution)
A8 A9 A10 A11 A12
B8 B9 B10 B11 B12
C8 C9 C10 C11 C12
D8 D9 D10 D11 D12
A4 B4 A5 B5 A6
A4 C4 A5 C5 A6
A4 D4 A5 D5 A6
B4 C4 B5 C5 B6
B4 D4 B5 D5 B6
C4 D4 C5 D5 C6
A2 B2 C2 D2 A3
A13 A14 A15 A16
B13 B14 B15 B16
C13 C14 C15 C16
D13 D14 D15 D16
B6 A7 B7 A8
C6 A7 C7 A8
D6 A7 D7 A8
C6 B7 C7 B8
D6 B7 D7 B8
D6 C7 D7 C8
B3 C3 D3 A4