4.1 Output Structure crono_packet¶

struct crono_packet¶

uint8_t channel¶

Source channel of the data.

Values correspond to the following:

0x0 – 0x3: ADC A – D

≥ 0x4: TDC channels. Which specific TDC channel is encoded in crono_packet::data.

uint8_t card¶: ID of the card.

uint8_t type¶

Type of the packet.

Different packet types correspond to different encodings of crono_packet::data.

Is one of the following:

CRONO_PACKET_TYPE_16_BIT_SIGNED¶

Used for ADC data.

crono_packet::data must be cast to int16_t and crono_packet::length must be multiplied by 4.

CRONO_PACKET_TYPE_TDC_DATA¶

Used for TDC data.

crono_packet::data must be cast to uint32_t and crono_packet::length must be multiplied by 2.

CRONO_PACKET_TYPE_AVRG_DATA¶

Used for averaged ADC data.

crono_packet::data must be cast to uint32_t and crono_packet::length must be multiplied by 2.

uint8_t flags¶

Bit field of the following flags:

CRONO_PACKET_FLAG_SHORTENED¶

Packet was truncated because internal FIFO was full.

This means that less than the requested number of samples have been written.

CRONO_PACKET_FLAG_PACKETS_LOST¶

Lost triggers preceeded this packet due to insufficient DMA buffers.

The DMA controller has discarded packets due to the full host buffer.

CRONO_PACKET_FLAG_OVERFLOW¶: The packet contains ADC sample overflows.

CRONO_PACKET_FLAG_TRIGGER_MISSED¶

Lost triggers preceeded this packet due to insufficient buffers.

The trigger unit has discarded packets due to a full FIFO.

CRONO_PACKET_FLAG_DMA_FIFO_FULL¶

The internal DMA FIFO was full.

Triggers only got lost if a subsequent package has crono_packet::flags with a bit weight CRONO_PACKET_FLAG_TRIGGER_MISSED set.

CRONO_PACKET_FLAG_HOST_BUFFER_FULL¶

The host buffer was full.

Triggers only got lost if a subsequent package has crono_packet::flags with a bit weight CRONO_PACKET_FLAG_TRIGGER_MISSED set.

CRONO_PACKET_FLAG_TDC_NO_EDGE¶

The packet from a TDC does not contain valid data.

Hence, the timestamp is not corrected. No valid edge was found for the TDC.

For TDC data, can also be one of the following:

NDIGO6G12_TDC_PACKET_FLAG_RESERVED¶

NDIGO6G12_TDC_PACKET_FLAG_CONTAINS_DATA¶: Packet contains at least one TDC event.

NDIGO6G12_TDC_PACKET_FLAG_LOST¶: At least one packet was lost due to full FIFO.

NDIGO6G12_TDC_PACKET_FLAG_SHORTENED¶: The trigger unit has shortend the current packet due to full FIFO.

NDIGO6G12_TDC_PACKET_FLAG_DMA_FIFO_FULL¶

The DMA FIFO was full.

Trigger only got lost if a subsequent package has crono_packet::flags with a bit weight NDIGO6G12_TDC_PACKET_FLAG_LOST set.

NDIGO6G12_TDC_PACKET_FLAG_HOST_BUFFER_FULL¶

The host buffer was full.

Trigger only got lost if a subsequent package has crono_packet::flags with a bit weight NDIGO6G12_TDC_PACKET_FLAG_LOST set.

uint32_t length¶: Length of crono_packet::data in multiples of 64 bits. The actual length of crono_packet::data depends on crono_packet::type.

uint64_t timestamp¶

Timestamp of the packet.

For the Ndigo6G-12, this corresponds to the beginning of the packet data.

uint64_t data[1]¶

Payload data of the packet.

The length of data corresponds to crono_packet::length.

The data type must be cast according to crono_packet::type, and the data encoding also depends on crono_packet::type.

See Section 4.3 for the data encoding of ADC data.

See Section 4.4 for the data encoding of TDC data.

See Section 4.5 for the data encoding of averaged ADC data.