Dadatrigger
This code is written for the AA-Alert project. (c) 2017 Jisk Attema, Netherlands eScience Center, ASTRON
Based on the PSRdada software.
Initial version of data flow pipeline
This is a work in progress; see the start.sh script.
Documentation and instructions coming soon(ish).
DADA header information
Meta data for the generated output is taken from various locations:
- the FITS file templates
- commandline arguemnts
- DADA header blocks
The start.sh script should get most values from the system (via QPID?), generates the necessary dada headers, and passes commandline arguments.
The table below describes the required keys in the DADA headerblock:
| DADA header key | used by | standard name (QPID?) | description | Units |
|---|---|---|---|---|
| NCHAN | filterbank, amber | NCHANNELS | Number of frequency channels | 1 |
| MIN_FREQUENCY | filterbank, fits, amber | Lowest frequency | ||
| CHANNEL_BANDWIDTH | filterbank, fits, amber | Bandwidth per channel | ||
| BW | filterbank | Total bandwidth | ||
| TSAMP | filterbank, amber | s | ||
| RA | filterbank | |||
| DEC | filterbank | |||
| SOURCE | filterbank | Name of the source | - | |
| AZ_START | filterbank | |||
| ZA_START | filterbank | |||
| MJD_START | filterbank | |||
| NBIT | filterbank | 1 | ||
| FILE_SIZE | dbdisk | Expected final file size (?) | bytes | |
| SAMPLES_PER_BATCH | amber | Normally 12500 or 25000 | 1 | |
| UTC_START | dbevent, dbdisk | Start of the observation | %Y-%m-%d-%H:%M:%S (UTC) | |
| RESOLUTION | dbevent | Page size (events are an integer mulitple of this) | bytes | |
| BYTES_PER_SECOND | dbevent | Data rate | bytes |
TODO:
- MIN_FREQUENCY, CHANNEL_BANDWIDTH, NCHAN, TSAMP, NBIT are all constant per experiment (ie. defined as part of the science case and mode). Having them as a parameter here is confusing, because changing it here will at most crash the codes; it will not do what you want.
- Link stuff to QPID
- Are we missing keys?