TADCTrigger

Group Number

UChar_t GetGroupNumber()

Number of this group (0-3) within the ADC board.

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Start Index Cell

UShort_t GetStartIndexCell()

Start Index Cell (SIC) is used to map sample indexes to the corresponding physical capacitor on the DRS4 chip, e.g. SIC=27 means that sample 0 was read from capacitor number 27 in the DRS4 capacitor array, sample 1 from capacitor 28, and so on. This information is mainly used to apply capacitor-related corrections to the raw readings from the V1742 and is usually not needed for off-line analysis.

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Sampling Frequency

UChar_t GetFrequency()

2 bit (0-3) code for frequency at which data was sampled.

• 0: 5 GHz
• 1: 2.5 GHz
• 2: 1 GHz
• 3: not used (will be used for 800 MHz sampling frequency when available)

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Trigger Signal Readout

Bool_t GetTriggerSignal()

Trigger signal sampling enable status (true: enabled, false: disabled). It is usually enabled.

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Trigger Time Tag

UInt_t GetTriggerTimeTag()

Trigger arrival time since last ADC board reset. Time is in 8.5ns clock counts.

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Trigger Sample Values

UShort_t GetNSamples()
Short_t  GetSample(Int_t)
Short_t* GetSamplesArray()

If Trigger Signal Readout is enabled, number of samples is 1024, 0 otherwise.

User can retrieve either the value of a single sample (GetSample), or an array with all the 1024 sample values (GetSamplesArray).

Sample values can exceed the 12 bit (0-4095) range due to CAEN V1742 correction algorithm. They are therefore encoded into a signed 16 bit variable (Short_t).