LCLS-II DAQ
Description of States
- Reset: initial state of the system, jump to this state from any other state to recover from (some) errors
- Unallocated: the state of the system before any detectors are allocated to participate in the DAQ. The "roll call" transition is used (often repeatedly, on a timer) to query the available detectors, which can take some time if not all detector executables are running yet
- Allocated: the state the system goes into after the user has selected which detectors they would like to use in the DAQ
- Connected: the state of the system after all "connections" are made. This idea of "connection" is general: it represents network connections (infiniband, ethernet, zeromq) as well as connections of the timing system readout groups, for example
- Configured: the state of the system after configuring all selected detectors (often a time-consuming step) or ending a run.
- Starting: this state is used to mark boundaries between scan-steps (where a motor is moved in coordination with pausing the DAQ)
- Paused: a state where the triggers to the system are disabled
- Running: the state where the DAQ is receiving per-shot data ("L1Accept"). The DAQ may also be configured to receive a low rate (~1Hz) of SlowUpdate transitions which are used to record slow epics data and other slow data (e.g. time tool backgrounds)
Description of Transitions
- Reset: x
- RollCall: x
- Alloc: x
- Dealloc: x
- Connect: x
- Disconnect: x
- Configure: x
- Unconfigure: x
- BeginRun: x
- EndRun: x
- BeginStep: x
- EndStep: x
- Enable: x
- Disable: x
- L1Accept: While in Running state, the DAQ receives per-shot data synchronized by the timing system hardware.
- SlowUpdate: While in Running state, the DAQ may be configured to generate a low rate (~1Hz) of SlowUpdate transitions which are used to record slow epics data and other slow data (e.g. time tool backgrounds). The timing of these transitions is not precise.
Overview
Content Tools