calix.spiking.correlation.AmplitudeCalib

class calix.spiking.correlation.AmplitudeCalib(target: Optional[Union[float, numpy.ndarray]] = 0.5, *, branches: calix.spiking.correlation.CorrelationBranches = <CorrelationBranches.CAUSAL: 1>, amp_calib: int = 0, time_calib: int = 0)

Bases: calix.common.base.Calib

Calibrate the correlation amplitude at delay zero.

Correlation traces are measured in a few quads in all CapMem quadrants. The median amplitude, extrapolated at a delay of zero, is estimated and the CapMem bias currents are tweaked accordingly.

Requirements: * CADCs are enabled and calibrated. * External correlation voltages (v_res_meas, v_reset) are set.

Variables

  • measurement – Instance of the correlation measurement class, used for measuring results.

  • quads – List of synapse quad column coordinates. Measurements from all rows in those quads are taken as an estimate for the characteristics of the whole quadrant. All quads in the list are located in quadrant 0, the measurement is repeated in the other quadrants using corresponding offsets to the coordinates.

  • log – Logger used to log outputs.

  • branches – Correlation branch to consider. Choose from causal, acausal or both, using the Enum CorrelationBranches.

  • parameters – Last configured CapMem parameters.

__init__(target: Optional[Union[float, numpy.ndarray]] = 0.5, *, branches: calix.spiking.correlation.CorrelationBranches = <CorrelationBranches.CAUSAL: 1>, amp_calib: int = 0, time_calib: int = 0)
Parameters

  • target – Target amplitude per correlated event.

  • amp_calib – Amplitude calibration setting to use in all synapses during measurement.

  • time_calib – Time constant calibration setting to use in all synapses during measurement.

  • capmem_current_low – Threshold to consider a current generated by the CapMem low. During calibration, the current will be increased in case amplitudes cannot be measured as expected. If the result contains low currents, a warning will be logged.

Methods

__init__([target, branches, amp_calib, …])

param target

Target amplitude per correlated event.

configure_parameters(builder, parameters)

Configure the given store bias currents in the given builder.

measure_results(connection, builder)

Estimate correlation parameters of each quadrant.

postlude(connection)

Log a warning in case resulting CapMem currents are low.

prelude(connection)

Preconfigure the chip for correlation measurements.
configure_parameters(builder: calix.common.base.WriteRecordingPlaybackProgramBuilder, parameters: numpy.ndarray) → calix.common.base.WriteRecordingPlaybackProgramBuilder

Configure the given store bias currents in the given builder.

Parameters

  • builder – Builder to append configuration instructions to.

  • parameters – Correlation store bias current for each quadrant.

Returns

Builder with configuration appended.

measure_results(connection: pyhxcomm_vx.ConnectionHandle, builder: calix.common.base.WriteRecordingPlaybackProgramBuilder) → numpy.ndarray

Estimate correlation parameters of each quadrant.

Parameters

  • connection – Connection to the chip to run on.

  • builder – Builder to run before measurements.

Returns

Array of each quadrant’s amplitudes.

postlude(connection: pyhxcomm_vx.ConnectionHandle) → None

Log a warning in case resulting CapMem currents are low.

Parameters

connection – Connection to the chip to be calibrated.

prelude(connection: pyhxcomm_vx.ConnectionHandle) → None

Preconfigure the chip for correlation measurements.

Parameters

connection – Connection to the chip to run on.