Payload Types - Hits

The following hit and trigger types are currently supported by payload-parsing. Below are the byte maps for the various payloads. This information is likely incomplete, as it is derived from the code and previous docs were quite out of date… Additional payload mapping information can be found here.

Type 10

The V2-4 engineering format DOM hit (a DOM hit which is either passed to the StringHub’s back-end Sender class or which is saved to a HitSpool file).

Byte Location

Length

Description

32

4

MBID

48

4

DOM Launch Time

58

2

Raw Format Information

60

1

ATWD ID

61

1

FADC Payload Length

62

1

ATWD format flag byte #0 - controls ch0/1

63

1

ATWD format flag byte #1 - controls ch2/3

64

1

Trigger Type

65

1

Padding Byte

66

6

DOM clock as 6 bytes in MSB order

72

N

FADC Samples

72 + N

M

ATWD Samples

Type 11

A composite container for DOM readout data.

Byte Location

Length

Description

0

4

Payload Length

4

4

Payload ID (value = 11)

8

8

Payload Time

16

2

RecType

18

2

UID

22

2

Payload Number

24

2

Payload Last

26

4

Source ID Number

30

8

Start Time

38

8

End Time

46

4

Length of composite payload

50

2

Type of composite payload (always seems to be ‘1’)

52

2

N of Composite Payloads

54

Variable

Bunch of payloads of type ‘10’ (the engineering data) or type ‘18’ (the delta-compressed data).

Type 18

A V2-4 delta-compressed payload.

Byte Location

Length

Description

8

8

DOM Launch Time

28

8

MBID

40

2

HitFlag

50

4

WORD1 from the compressed data

54

4

WORD3 from the compressed data

58

Varies

N compressed words encoded in WORD1

WORD1 and WORD3 are described in this document. They have the following bit format.

WORD1

Bit Position

Length

Description

31

1

Compression Flag

30

1

Minimum Bias Flag

29

12

Trigger Word

17

2

Local Coincidence (01 below, 10 above, 11 below and above)

15

1

fADC available

14

1

ATWD available

13

2

ATWD Size

11

1

ATWD A or B

10

11

Hit Size

WORD3

Bit Position

Length

Description

31

1

Peak Range

30

4

Peak Sample

26

9

Pre-Peak Count

17

9

Peak Count

8

9

Post-Peak Count

Type 25

The V5 delta-compressed hit records including OMKeys, and the HitFlags.

Byte Location

Length

Description

2

1

Hit Record Type (should be 1)

3

1

HitFlags

4

2

ChannelID

6

4

DOM Launch Time

10

4

WORD1 from the compressed data

14

4

WORD3 from the compressed data

18

Varies

N compressed words encoded in WORD1

Type 26

The V5 engineering hit records, concise format.

Byte Location

Length

Description

2

1

Hit Record Type (should be 1)

3

1

HitFlags

4

2

ChannelID

6

4

DOM Launch Time

10

1

ATWD ID

11

1

FADC Payload Length

12

N

FADC Samples

12 + N

M

ATWD Samples

Type 27

The V6 delta-compressed hit records.

Byte Location

Length

Description

3

1

HitFlags

4

2

ChannelID

6

4

DOM Launch Time

10

4

WORD1 from the compressed data

14

4

WORD3 from the compressed data

18

Varies

N compressed words encoded in WORD1

Payload Types - Triggers

Payloads encapsulating trigger requests.

Type 9

Triggers payload for V2 events.

Byte Location

Length

Description

0

4

Payload Length

4

4

Payload ID (value=9)

8

8

Payload Time

16

2

Rec Types (?)

18

4

UID (?)

22

4

Trigger Types

26

4

Trigger Config ID

30

4

Source ID

34

8

Trigger Start Time

42

8

Trigger End Time

50

2

Readout Request Types

52

4

Trigger UID

56

4

Source ID

60

4

N ReadoutRequestElementRecords (see below)

64

32 * N

Bundle of ReadoutRequestElementRecord

64 + 32 * N

4

Length of composite records

68 + 32 * N

2

Composite Types (value=1)

70 + 32 * N

4

Number of Composite Payloads of type ‘9’.

ReadoutRequestElementRecord

Byte Location

Length

Description

0

4

Readout Types

4

4

Source ID

8

8

Trigger Start Time

16

8

Trigger End Time

24

8

DOM ID

Type 91

Triggers payload for V5 or V6 events.

Byte Location

Length

Description

0

4

Trigger Type

4

4

Trigger Configuration ID

8

4

Trigger Source ID

12

4

Trigger Start Time

16

4

Trigger End Time