Signal Sequences
Normal triggers does not set Special Events field of CIn. The signal sequence is as follows:
2 ENG sets Busy Event Gen in COut
4 ENG transfers Event#&Type to all ROCs via DIO
5 ENG waits falling edge of all Busy ROCs
6 each ROC receives Event#&Type
7 each ROC sets Busy ROC in CIn of ENG
8 each ROC buffers event data
9 each ROC removes Busy ROC in CIn of ENG
10 ENG detects removal of all Busy ROCs
11 ENG removes Busy Event Gen in CIn
Let’s consider TOF LED Pulser. The hardware trigger is applied to the Calibration Trigger part of the trigger logic. The signal from the corresponding bit of the LVL0 TR goes to the TOF LED input of the control input port (CIn) ENG. The bit pattern of the Special Events field of CIn is transferred to the EventType field of data port DIO.
Actually the ROC should turn off the zero-suppression before the event arrival. If we need to mix zero-suppressed events with non zero-suppressed in one run then TOF ROC should control the Pedestal Pulser like follows:
1 TOF ROC generates Busy ROC
2 TOF ROC turn off zero suppression
3 TOF ROC removes Busy ROC
4 TOF ROC generates Pedestal Pulser by writing to the local COut