Output data structure in CODA

From PolWiki
Jump to navigationJump to search

The electron detector readout boards(v1495) are currently outputting data in the following format:

Event types defined

 Event type 1 : Helicity Reversal events
 Event type 2 : photon single events
 Event type 3 : electron single events
 Event type 4 : coincidence of electron and photon single events

Sub banks used

 Single Event Data from Slave-1: 0x201
 Single Event Data from Slave-2: 0x202
 Single Event Data from Slave-3: 0x203
 Accumulation Data from Slave-1 : 0x204
 Accumulation Data from Slave-2 : 0x205
 Accumulation Data from Slave-3 : 0x206

If the TS2 did not receive either of the type-1 or type-4 triggers then the message logger will start printing "Event type and number are:" followed by the value assigned to the variable event_ty

Structure inside Accumlator subbank

The data from s1 is prefixed by 0xACCBCDEF1 followed by 32 words each having 32 bits(with only the 12 least significant bits being relevant), this is then suffixed by 0xACCFEDCB1

Similarly, data from s2 is prefixed by 0xACCBCDEF2 followed by 32 words and suffixed by 0xACCFEDCB2 and the data from s3 is prefixed by 0xACCBCDEF3 followed by 32 words suffixed by 0xACCFEDCB3.

Structure inside single-event subbank

The single event data of s1 is prefixed by 0xAABBDDE1 followed by 4 words each having 4 words 32 bit. The 1st, 2nd, 3rd and 4th words tells the hit-pattern as recorded by the top 32 channels of plane 1, 2, 3 and 4 respectively. These 4 words are then suffixed by 0xEEDDBBA1

Following the above pattern, the single event data of s2 is prefixed by 0xAABBDDE2 and suffixed by 0xEEDDBBA2; whereas the single event data from s3 is prefixed by 0xAABBDDE3 and suffixed by 0xEEDDBBA3.

These patterns and numbers can be changed with ease, but this is the format in which the most recent data files are found.