FASTBUS data stream.
The data from the FASTBUS crate are merged with the silicon data in the Event Builder (EB). In the merged data, the start of the FASTBUS data is indicated by a 0xda0000aa word. The end of the FASTBUS data is indicated by a 0xda0000bb word.
The FASTBUS data stream consists of information from the LeCroy 1881M ADCs and the LeCroy 1875A TDCs. The current layout of the FASTBUS crate, and the physical location of the ADCs and TDCs is shown in Figure 1. The slot assignments for the various modules are listed in Table 1.
The start and end of the FASTBUS data stream are indicated by 0xda0000aa and 0xda0000bb, respectively. The FASTBUS raw data format is shown in Table 2.
Data stream from ADCs.
The data for each ADC are read out using a single call in the CODA crl:
block read 100 from geo data ADC_SLOT
where ADC_SLOT is the slot number of the ADC. This call will return a 32-bit header word and between 0 and 64 32-bit data words.
Data stream from TDCs.
The data for each TDC are read out using a single call in the CODA crl:
block read 100 from geo data TDC_SLOT
where TDC_SLOT is the slot number of the TDC. This call will return between 0 and 64 32-bit data words (note: no header words are generated).
Figure 1. Layout of FASTBUS crate.
Last Updated on 3/21/99
By Frank L. H. Wolfs