Lava Interfaces

fugu.backends.lava_interfaces.calculate_bit_length(value)

fugu.backends.lava_interfaces.calculate_weight_exponent(weights)

fugu.backends.lava_interfaces.calculate_hardware_weights(weights, weight_exponent)

class fugu.backends.lava_interfaces.LoihiInterface(duration)

Bases: ABC

THRESHOLD_BIT_LIMIT = 22

MAX_DELAY_VALUE = 63

A note about max delay values: The reason why we are setting this to 63 is not entirely clear: 1) The lava documentation for the bit-acc Python model of the DelaySparse/Dense connections explicity set 63 as themaximum value. 2) Looking at the source code for the neuro-core model for the Delay connections, the code checks to see if the bit_length of the max delay is < 6. This would suggest that the max delay should be 31.

HOWEVER, empirically the maximum delay value of the default Delay connections is 63. This implies that the hardware (or at least lava) does some sort of shifting to delay values prior to checking.

Another note: The non-bit-acc Python model does not seem to have the same restrictions. But we will us a default value of 63.

abstract setup_input_process(input_iterator, scale_factor)

abstract setup_output_process(output_processes)

abstract get_config(callback_functions=[])

abstract get_lif_process(count, initial_voltages, spike_threshold, decay_constant, bias_mants, name)

abstract connect_input_to_lif(input_weights, input_delays, input_process, lif_data, lif_process)

abstract connect_lif_to_output(output_weights, lif_process)

abstract connect_lif_to_lif(source_lif_data, source_lif_process, dest_lif_data, dest_lif_process)

abstract setup_probe(var)

abstract get_spike_output(process_data)

abstract print_output_probe_data()

class fugu.backends.lava_interfaces.Loihi2SimInterface(duration)

Bases: LoihiInterface

CURRENT_DECAY_SCALE_FACTOR = 1

VOLTAGE_DECAY_SCALE_FACTOR = 1

setup_input_process(input_iterator, scale_factor)

setup_output_process(output_processes)

get_config(callback_functions=[])

get_lif_process(count, initial_voltages, spike_threshold, decay_constant, bias_mants, name)

connect_input_to_lif(input_weights, input_delays, lif_data, lif_process)

connect_lif_to_output(output_weights, lif_process)

connect_lif_to_lif(source_lif_data, source_lif_process, dest_lif_data, dest_lif_process)

get_pass_through_weights(lif_data, weight_scale_factor)

setup_probe(var)

get_spike_output(process_data)

print_output_probe_data()

class fugu.backends.lava_interfaces.Loihi2SimBitAccInterface(duration)

Bases: Loihi2SimInterface

THRESHOLD_BIT_LIMIT = 16

CURRENT_DECAY_SCALE_FACTOR = 4095

VOLTAGE_DECAY_SCALE_FACTOR = 4096

setup_output_process(output_processes)

get_config(callback_functions=[])

get_lif_process(count, initial_voltages, spike_threshold, decay_constant, bias_mants, name)

connect_input_to_lif(input_weights, input_delays, lif_data, lif_process)

connect_lif_to_output(output_weights, lif_process)

connect_lif_to_lif(source_lif_data, source_lif_process, dest_lif_data, dest_lif_process)

class fugu.backends.lava_interfaces.Loihi2HWInterface(duration)

Bases: LoihiInterface

CURRENT_DECAY_SCALE_FACTOR = 4095

VOLTAGE_DECAY_SCALE_FACTOR = 4096

format_matrix(m)

setup_input_process(input_iterator, scale_factor)

setup_output_process(output_processes)

get_config(callback_functions=[])

get_lif_process(count, initial_voltages, spike_threshold, decay_constant, bias_mants, name)

connect_input_to_lif(input_weights, input_delays, lif_data, lif_process)

connect_lif_to_output(output_weights, lif_process)

connect_lif_to_lif(source_lif_data, source_lif_process, dest_lif_data, dest_lif_process)

get_pass_through_weights(lif_data, weight_scale_factor)

setup_probe(var)

get_spike_output(process_data)

print_output_probe_data()