calix.common.madc_base.Recorder

class calix.common.madc_base.Recorder

Bases: abc.ABC

Abstract base class for experiments/calibrations which use the MADC.

During prepare_recording(), the MADC is enabled and the current readout section config is saved. During recording, the readout config is changed continuously to measure one neuron’s properties after another. Furthermore, a stimuli can be injected during the measurement to observe the neurons’ responses and the recording timing per neuron can be set.

Variables

• original_readout_config – Source selection mux config before start of the experiment. Used to restore state after the experiment has finished.

• original_neuron_configs – Neuron configs before start of the experiment. Used to restore state after the experiment.

• sampling_time – Time to record MADC samples for each neuron. The requested sampling time must be achievable with the maximum number of samples in the MADCConfig - without using continuous sampling. With default settings, this equals roughly 2.18 ms of recording time per neuron.

• _wait_before_stimulation – Time to wait after triggering MADC sampling before stimulation. Marked private since analyzing the trace is typically not robust against changing this number.

• dead_time – Time to wait before triggering the MADC sampling after the previous sampling period ended. Within this time, the neuron connections are changed. A minimum of 1 us is recommended.

• wait_between_neurons – Total time to wait for samples for each neuron. Has to be larger than the sum of sampling_time, wait_before_stimulation and dead_time.

• madc_input_frequency – Expected input clock frequency for the MADC, supplied by the PLL. Defaults to 500 MHz, which is present after the default stadls ExperimentInit.

• madc_config – Static configuration of the MADC. Written during prepare_recording() and used to obtain the sample rate. The number of samples is calculated automatically based on the sampling_time.

• invalid_samples_time – Timeframe in the beginning of a trace that is considered invalid. The MADC will start recording samples, but only after this time has elapsed, the sampling_time starts and samples are returned. This works around a bug, see issue 4008 for details.

__init__()

Initialize self. See help(type(self)) for accurate signature.

Methods

__init__()	Initialize self.
build_measurement_program(builder)	Builds a program to measure an arbitrary MADC trace for each neuron.
neuron_config_disabled(neuron_coord)	Return a neuron config in silent state, i.e. disconnected from the common readout lines.
neuron_config_readout(neuron_coord)	Return a neuron config with readout active and connected to the readout lines.
prepare_recording(connection)	Prepares chip for the experiment.
record_traces(connection, builder)	Executes measurement on chip, returns samples per neuron.
restore_initial_state(connection)	Restore original readout and neuron configuration.
stimulate(builder, neuron_coord, …)	Execute some commands after triggering MADC sampling.

build_measurement_program(builder: calix.common.base.WriteRecordingPlaybackProgramBuilder) → Tuple[calix.common.base.WriteRecordingPlaybackProgramBuilder, List[pystadls_vx_v3.ContainerTicket]]

Builds a program to measure an arbitrary MADC trace for each neuron.

One neuron after another is connected to the MADC, the stimulate function is called and samples are recorded. The timing of each neuron is recorded, tickets containing the start and stop of the recording time are returned along with the builder.

Parameters

builder – Builder to append instructions to.

Returns

Tuple containing: * Builder with instructions appended. * List of read tickets marking start and end of the

recording of each neuron.

abstract neuron_config_disabled(neuron_coord: pyhalco_hicann_dls_vx_v3.NeuronConfigOnDLS) → pyhaldls_vx_v3.NeuronConfig

Return a neuron config in silent state, i.e. disconnected from the common readout lines.

Parameters

neuron_coord – Coordinate of neuron to get config for.

Returns

Neuron config with readout disabled.

abstract neuron_config_readout(neuron_coord: pyhalco_hicann_dls_vx_v3.NeuronConfigOnDLS) → pyhaldls_vx_v3.NeuronConfig

Return a neuron config with readout active and connected to the readout lines.

Parameters

neuron_coord – Coordinate of neuron to get config for.

Returns

Neuron config with readout enabled.

prepare_recording(connection: pyhxcomm_vx.ConnectionHandle)

Prepares chip for the experiment.

Configures the MADC and sets necessary bias currents. Reads and saves readout config and neuron config to restore original state after the experiment.

Parameters

connection – Connection to the chip.

record_traces(connection: pyhxcomm_vx.ConnectionHandle, builder: calix.common.base.WriteRecordingPlaybackProgramBuilder) → List[numpy.ndarray]

Executes measurement on chip, returns samples per neuron.

Parameters

• connection – Connection to the chip to calibrate.

• builder – Builder to append measurement program to.

Returns

List of numpy arrays, containing samples for each neuron.

Raises

TooFewSamplesError – If the number of received MADC samples is significantly smaller than expected for at least one neuron. The evaluate function may fail in this case, thus the error is caught here.

restore_initial_state(connection: pyhxcomm_vx.ConnectionHandle)

Restore original readout and neuron configuration.

Parameters

connection – Connection to the chip to calibrate.

abstract stimulate(builder: calix.common.base.WriteRecordingPlaybackProgramBuilder, neuron_coord: pyhalco_hicann_dls_vx_v3.NeuronConfigOnDLS, stimulation_time: pyhaldls_vx_v3.Timer.Value) → calix.common.base.WriteRecordingPlaybackProgramBuilder

Execute some commands after triggering MADC sampling.

E.g., synaptic inputs could be sent to observe their shape.

Parameters

• builder – Builder to append stimulation instructions to.

• neuron_coord – Coordinate of neuron which is currently recorded.

• stimulation_time – Timer value at beginning of stimulation.

Returns

Builder with stimulation instructions appended.