Trip-T Front End Board Documentation Home
TFB Operation
Initialisation
After power up or reset, the TFB registers will contain mostly
zeros. Before operation certain registers must be written to, this
sequence is discussed below. Failure to do this will result in
undesired behaviour upon triggering.
- Set up return clock phase.
- Set up High Voltage trims
- Write to the integration time register
- Write to the pre reset time register
- Set the discriminator channel masks.
- Set the Tript-T Enable register
- Write to the Trip-T register space
- Set up any test/calibration trigger offsets required.
- Change the mode from Trip-T configuration to operation.
The register space can be accessed at will. It's not advisable to
change values such as the integration time during active periods of
operation, though these values can be non-destructively read
back. When not active, any register may be updated. It's not necessary
to reload every register value if doing, e.g. scan of the high voltage
trim.
Running
When triggered, the TFB operation FSM will sequence the TripT and
place the data generated into the readout buffers ready for
readout. In single spill with data packet management, once a spill is
complete the TFB will await readout triggers. Once all the data
packets have been readout, the device may be re-triggered either by
the configuration bus route, or the hardware trigger line. If a
trigger is issued before the readout is complete the buffers will
overflow and data loss will occur. At the time of writing, the TFB
doesn't handle this situation elegantly and it will cause the readout
mux to lock up. Recovery from this situation will require a reset.