def test_SweepNeurons(self):
"""When the exponential term of a neuron is disabled and firing is off
V_t should not have any effect on the rest potential."""
# FIXME: Differs from HICANN to HICANN, this needs connection database
analog = Coordinate.AnalogOnHICANN(0)
adc_channel = 3
bigcap = True
trace_length = 1950
neurons = [Coordinate.NeuronOnHICANN(Enum(ii)) for ii in range(512)]
threshold_voltages = np.arange(0, 1024, step=20, dtype=np.ushort)
membrane = np.zeros((len(neurons), threshold_voltages.size))
nconf = HICANN.NeuronConfig()
nconf.bigcap[int(top)] = bigcap
nconf.bigcap[int(bottom)] = bigcap
HICANN.set_neuron_config(self.h, nconf)
for ii, V_t in enumerate(threshold_voltages):
fgctrl = HICANN.FGControl()
for nrn in neurons:
fgctrl.setNeuron(nrn, HICANN.neuron_parameter.V_t, V_t)
fgctrl.setNeuron(nrn, HICANN.neuron_parameter.I_bexp, 0)
for block in [
Coordinate.FGBlockOnHICANN(Enum(xx)) for xx in range(4)
]:
HICANN.set_fg_values(self.h, block, fgctrl.getBlock(block))
for jj, neuron in enumerate(neurons):
self.set_denmem_quads(neuron, enable_aout=True)
self.set_analog(analog, neuron)
trace, v, t = self.get_trace(adc_channel, trace_length)
membrane[jj, ii] = v.mean()
if False:
import pylab
import matplotlib
fig, ax = pylab.subplots()
cax = ax.imshow(membrane.T,
interpolation='nearest',
cmap=matplotlib.cm.coolwarm)
fig.colorbar(cax, orientation='horizontal')
fig.show()
# Case 1: Radically different behaviour between upper neurons and lower neurons.
std = membrane.std(axis=1)
self.assertAlmostEqual(std[:256].mean(), std[256:].mean(), places=2)
# Case 2: Ideally we would want uniform behaviour for all values of V_t.
self.assertLess(membrane.mean(axis=0).std(), 0.05)
def test_BGToNeuronMembrane(self):
"""Try to send periodic events from a background generator to a neuron.
Please note that this test relies on the default config values in most objects
and only changes those necessary to run the test."""
weight = 15
period = 700 * 2
event = HICANN.L1Address(0)
offevent = HICANN.L1Address(55)
trace_length = 19500
exc = True
inh = False
E_syn = (570, 570)
firing = False
firingevent = HICANN.L1Address(42)
# FIXME: Differs from HICANN to HICANN, this needs connection database
analog = Coordinate.AnalogOnHICANN(1)
adc_channel = 7
neuron = Coordinate.NeuronOnHICANN(Enum(15))
vline = Coordinate.VLineOnHICANN(28) # or 60, 92, 124
driver = Coordinate.SynapseDriverOnHICANN(Y(111), left)
synapse_row = Coordinate.SynapseRowOnHICANN(driver, top)
##############################
# set floating gate values #
##############################
fgcfg = HICANN.FGConfig()
fgctrl = HICANN.FGControl()
# Set same reverse potential for both synaptic inputs (for all neurons)
for ii in range(512):
nrn = Coordinate.NeuronOnHICANN(Enum(ii))
fgctrl.setNeuron(nrn, HICANN.neuron_parameter.E_synx, E_syn[0])
fgctrl.setNeuron(nrn, HICANN.neuron_parameter.E_syni, E_syn[1])
fgctrl.setNeuron(nrn, HICANN.neuron_parameter.I_bexp, 0)
for block in Coordinate.iter_all(Coordinate.FGBlockOnHICANN):
HICANN.set_fg_config(self.h, block, fgcfg)
HICANN.set_fg_values(self.h, fgctrl)
##############################
# set global neuron config #
##############################
nconf = HICANN.NeuronConfig()
nconf.bigcap[int(top)] = True
nconf.bigcap[int(bottom)] = True
HICANN.set_neuron_config(self.h, nconf)
#################
# set mergers #
#################
dnc = HICANN.DNCMergerLine()
for i in range(8):
mer = Coordinate.DNCMergerOnHICANN(i)
dnc[mer].slow = True
dnc[mer].config = HICANN.Merger.RIGHT_ONLY
# Tree defaults to one on one passthrough (forward downwards)
tree = HICANN.MergerTree()
HICANN.set_dnc_merger(self.h, dnc)
HICANN.set_merger_tree(self.h, tree)
##########################
# background generator #
##########################
# We use one background generator to provide events
gens = HICANN.BackgroundGeneratorArray()
g = gens[7]
g.enable(True)
g.random(False)
g.period(period)
g.address(event)
HICANN.set_background_generator(self.h, gens)
# Forward its output to this HICANN
srepeater = Coordinate.OutputBufferOnHICANN(7).repeater()
sr = HICANN.HorizontalRepeater()
sr.setOutput(right)
HICANN.set_repeater(self.h, srepeater.horizontal(), sr)
###############################################
# connect via Crossbars and SynapseSwitches #
###############################################
hline = srepeater.toHLineOnHICANN()
cb = HICANN.Crossbar()
cb.set(vline, hline, True)
HICANN.set_crossbar_switch_row(
self.h, hline, vline.toSideHorizontal(),
cb.get_row(hline, vline.toSideHorizontal()))
# Connect VLine to synapse driver
sw = HICANN.SynapseSwitch()
sw.set(vline, driver.toHLineOnHICANN(), True)
HICANN.set_syndriver_switch_row(
self.h, driver.toSynapseSwitchRowOnHICANN(),
sw.get_row(driver.toSynapseSwitchRowOnHICANN()))
########################
# set synapse driver #
########################
drv = HICANN.SynapseDriver()
drv.set_l1()
drv[top].set_syn_in(left, exc)
drv[top].set_syn_in(right, inh)
drv[bottom].set_syn_in(left, exc)
drv[bottom].set_syn_in(right, inh)
HICANN.set_synapse_driver(self.h, driver, drv)
decoders = HICANN.DecoderDoubleRow()
weights = HICANN.WeightRow()
# Reset decoders and weights to 'off' state
for ii in range(2):
for jj in range(256):
decoders[ii][jj] = offevent.getSynapseDecoderMask()
for ii in range(256):
weights[ii] = 0
# Only enable decoders/weights for background generator and neuron
decoders[0][int(neuron.x())] = event.getSynapseDecoderMask()
weights[int(neuron.x())] = weight
HICANN.set_decoder_double_row(self.h, driver, decoders)
HICANN.set_weights_row(self.h, synapse_row, weights)
###################
# get ADC trace #
###################
self.set_denmem_quads(neuron,
address=firingevent,
activate_firing=firing,
enable_aout=True)
self.set_analog(analog, neuron)
trace, v, t = self.get_trace(adc_channel, trace_length)
if False:
import pylab
fig, ax = pylab.subplots()
ax.plot(t, v)
pylab.show()
## Case 1: Sometimes the membrane seems 'stuck' at 1.2V
self.assertNotAlmostEqual(v.mean(), 1.2, places=1)
self.assertGreater(v.std(), 0.01)