Figure 2.

The schematic visualization of neurons (grey triangles), non-plastic and virtual synapses (white squares), as well as input-output interfaces and bias generator of the ROLLS chip. Each neuron on the chip (presynaptic neuron) sends its output spikes to 256 non-plastic synapses, which, if set active, can route these spikes to any of the neurons on the chip (postsynaptic neurons). The connectivity matrix allows for all-to-all connectivity, but also other configurations. AER is a digital Address-Event Representation, used to communicate spikes (it consists of an index of the spike-emitting neuron).