VME DAQ Rawdata Format

Raw data is stored as is from the hardware. Minimal quantum of data is 4 bytes (32 bits). Intel byte order is used.

Bit fields

Raw data word structure by bits, MSB left:

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

type

data

Type is one of the following:

type, bin

type, hex

code

description

0000

0

DATA

Module data

0001

1

0010

2

0011

3

0100

4

0101

5

0110

6

0111

7

1000

8

MHDR

Module header

1001

9

MTRL

Module trailer

1010

A

EHDR

Event header

1011

B

ETRL

Event trailer

1100

C

SHDR

Spill header

1101

D

STRL

Spill trailer

1110

E

STAT

Status

1111

F

DATA

16-bit module data

Structure

Raw data stream is split in spills beginning with SHDR and ending with STRL, the data in between is a sequence of zero or more events. Event begins with EHDR and ends with ETRL. The data between event header and trailer is a sequence of module data blocks. Module data starts with MHDR and ends with MTRL. Module data is any number of words of type DATA.

SHDR

STRL ...

Details

SHDR

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

1

1

0

0

0

spill type

reserved

STRL

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

1

1

0

1

0

spill type

reserved

Spill type:

EHDR

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

1

0

1

0

reserved

event number

ETRL

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

1

0

1

1

reserved

word count

MHDR

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

1

0

0

0

slot number

module ID

event number

MTRL

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

1

0

0

1

reserved

CBLT flags

reserved

word count

VmeDaqRawdataFormat (last edited 2008-12-12 10:51:22 by slepnev)