This is NOT a real instrument, but is treated as virtual instrument (added as one in qcodes). This is reponsible for timing of various instrument using pulse delay generator DG645 (thus it also uses DG645 module interally to give tirggers to different instruments accoding to given timings parameters.)
timingIt requires a pulse delay generator (DG645, aka pulser) object, PulseConfig object (pc) and FPGA object fpga.
from qcodes.instrument_drivers.sqdlab.TimingConfig import TimingConfig
timing = TimingConfig(
'timing', pulser,
fixed_point_get_cmd=pc.fixed_point,
awg_duration_get_cmd=pc.pattern_length,
acq_duration_get_cmd=lambda: 10e-9*fpga.tv_samples.get()*fpga.tv_decimation.get() if fpga.app.get() == b'tvmodev02' else None
)
There are 2 key componenet (classes) for whose parameters can configured:
Internally, TimingConfig adds 4 channels (sub_modules):
Usually, these channels are one of the channels or channel pairs of DG645
For each of these channels, there are Channel parameters.
There is also an option for setting reference points. There are 3 reference point possible:
| Reference point name | values |
|---|---|
| zero | 0 |
| awg output start | awg.trigger_delay.get() |
| fixed point | awg output start + self.fixed_point_get_cmd() |
Essentials:
| Parameters | Additional Info | Default Value |
|---|---|---|
| clock_interval | Interval between triggers RECEIVED BY the pulse generator | 200e-9 |
| repetition_time | Interval of the main trigger output (T0) by the pulse | (min_val = 0) |
Additionally, there are few function present in this class:
get_repetition_time(self):
Returns clock_interval * pulser.trigger_prescale_factor.
?Basically, it tells number of times pulser will send trigger per clock cycle.
set_repetition_time(self, value):
The value should be divisible by clock_interval .
check_repetition_time(self):
Returns True or False depending upon self.pulser.T0.duration.get() > self.repetition_time.get().
That is, the trigger cycle of pulser shoud NOT exceed the repetition time.
get_ref_points(self):
Returns a dictionary of all the three reference points mentioned above.
get_timings(self):
Returns a dictionary of all channels with their timings.
check_timing(self):
Internally checks for any inconsistency in timings for triggering various instruments.
update(self):
Push all the timing configuration to pulse delay generator (DG645).
plot(self):
Generate a representation of the timing configuration with matplotlib.
timing.clock_interval.set(1/5e6)
timing.update()
timing.plot()
timing.repetition_time.set(36e-6)
For each channel, there is the common parameterchannel , which can be set using:
timing.<channel name>_channel.set(<pulser/DG645 channel>)
# Example:
timing.acq_channel.set(pulser.AB)
timing.<channel name>_trigger_delay.set(<time in sec>)
# Example:
timing.awg_trigger_delay.set(310e-9)
timing.<channel name>_trigger_duration.set(<time in sec>)
# Example:
timing.awg_trigger_delay.set(310e-9)
This is the Time relative to which the in/output starts.
# Example:
timing.aux1.reference('awg output start')
offset:
In/output time offset from reference point.
trigger_holdoff:
Minimum time required before a trigger can be processed after in/output finishes.
If duration is NOT zero, then following parameter can also be used:
duration: get_timings(self, ref_points):
Input is dictionary of absolute times of all the 3 reference points mentioned above. Return a dictionary of out_start, out_end, trig_start, trig_end.
update(self, ref_points):
Push the channel timings to pulse generator (DG645).
WIHTOUT Instrument Wrapper [This is will be used in future]
from qcodes.instrument_drivers.sqdlab.TimingConfig import TimingConfig
timing = TimingConfig(
'timing', pulser,
fixed_point_get_cmd=pc.fixed_point,
awg_duration_get_cmd=pc.pattern_length,
acq_duration_get_cmd=lambda: 10e-9*fpga.tv_samples.get()*fpga.tv_decimation.get() if fpga.app.get() == b'tvmodev02' else None
)
# instrument timing for time dependendent measurements
#timing.clock_interval.set(1/10e6) # frequency on the pulser trigger input
timing.clock_interval.set(1/5e6)
timing.repetition_time.set(36e-6)
pc.pattern_length(10.1e-6)
pc.fixed_point(10e-6)
pc.separation(5e-9)
#fpga.tv_samples.set(180) # (acquisition time defaults to 4 * 10ns * samples)
timing.acq.channel.set(pulser.AB)
#fpga.trigger_acq_delay.set(10) # trigger holdoff in samples
#timing.acq.trigger_delay.set(10e-9*fpga.trigger_acq_delay.get())
timing.acq.trigger_delay.set(100e-9)
timing.acq.offset.set(0e-6)
timing.acq.trigger_duration.set(100e-9)
timing.readout.channel.set(pulser.CD)
timing.readout.trigger_duration.set(5e-6)
timing.readout.trigger_delay.set(34e-9)
timing.readout.offset.set(0)
# AWGs on T0 and EF
timing.awg.channel.set(pulser.T0)
timing.awg.trigger_delay.set(410e-9)
timing.aux1.channel.set(pulser.EF)
timing.aux1.reference('awg output start')
timing.aux1.trigger_delay(123e-9)
timing.aux1.trigger_duration.set(100e-9)
timing.aux2.channel.set(pulser.GH)
#timing.aux2.channel.set(None)
timing.aux2.trigger_duration.set(100e-9)
timing.update()
timing.plot()
This with Instrument wrapper enable
timing = Instrument(timing, 'timing')
timing.awg_fixed_point = pc.fixed_point
timing.awg_pattern_length = pc.pattern_length
timing.readout_duration = timing.duration_readout = timing.trigger_duration_readout = timing.readout_trigger_duration
rep_time = np.round(40e-6/100e-9//8)*100e-9*8 # used to be ceil
timing.repetition_time.set(float(rep_time)) # trigger prescale must be divisible by 8 for the AWGs
samples = 2**7
fpga.tv_samples.set(samples) # this sets the measurement time (decimation * 10 ns * # samples)
print('sample time = {0} us'.format(samples*10e-9*4*1e6))
pc.set('pattern_length', np.ceil(5.1e-6*(1.25e9//8))/(1.25e9//8))
#pc.pattern_length.set(5.1e-6)
pc.fixed_point.set(5e-6)
timing.readout_duration.set(5e-6) #sets length of MW cavity pulse
# calibration parameters -> setup dependent stuff!!
timing.acq_channel.set(pulser.AB)
fpga.trigger_acq_delay.set(5) # FPGA trigger to measurement delay. Measured in samples to avoid measuring the trigger through cross-talk
timing.acq_trigger_delay.set(10e-9*fpga.trigger_acq_delay.get()) # time btw fpga trigger and fpga measure
timing.acq_offset.set(-50e-9)
timing.readout_channel.set(pulser.CD)
timing.readout_trigger_delay.set(14e-9)
timing.readout_offset.set(-50e-9 + 220e-9)
#timing.awg_channel.set('')
#timing.awg_trigger_delay.set(260e-9)
timing.awg_channel.set(pulser.T0)
timing.awg_trigger_delay.set(310e-9) # data sheet says 540ns
# timing.aux1_channel.set(pulser.EF)
# timing.aux1_offset.set(200e-9)
pulser.EF.delay.set(220e-9)
#pulser.EF_delay.set(410e-9 - 260e-9)
timing.aux2_channel.set(None)
timing.update()
fig = timing.plot()