Cronologic xTDC4, Руководство пользователя

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3.6.2 Input Structure xtdc4 read out
crono packet *first packet
Pointer to the first packet that was capture by the call of xtdc4 read .
crono packet *last packet
Address of header of the last packet in the buffer.
int error code
Assignments of the error codes.
#define CRONO READ OK 0
#define CRONO READ NO DATA 1
#define CRONO READ INTERNAL ERROR 2
#define CRONO READ TIMEOUT 3
const char *error message
3.7 Packet Format
3.7.1 Output Structure crono packet
unsigned char channel
Unused, always 0.
unsigned char card
Identifies the source card in case there are multiple boards present. Defaults to 0 if no value is
assigned to the parameter
board id in Structure ndigo init parameters .
unsigned char type
The data stream consists of 32 bit unsigned data as signified by a value of 6.
unsigned char flags
#define XTDC4 PACKET FLAG ODD HITS 1
The last data word in the data array consists of one timestamp only which is located in the
lower 32 bits of the 64 bit data word (little endian).
#define XTDC4 PACKET FLAG SLOW SYNC 2
Start pulse distance is larger than the extended timestamp counter range.
#define XTDC4 PACKET FLAG START MISSED 4
The trigger unit has discarded packets due to a full FIFO.
#define XTDC4 PACKET FLAG SHORTENED 8
The trigger unit has shortend the current packet due to full FIFO.
#define XTDC4 PACKET FLAG DMA FIFO FULL 16
The internal DMA FIFO was full. Might or might not result in dropped packets.
#define XTDC4 PACKET FLAG HOST BUFFER FULL 32
The host buffer was full. Might or might not result in dropped packets.
unsigned int length
Number of 64-bit elements (each containing up to 2 TDC hits) in the data array.
unsigned int64 timestamp
cronologic GmbH & Co. KG 18 xTDC4 User Guide