  The BrainScaleS-2 (BSS-2) Neuromorphic Computing System currently consists of
multiple single-chip setups, which are connected to a compute cluster via
Gigabit-Ethernet network technology. This is convenient for small experiments,
where the neural networks fit into a single chip. When modeling networks of
larger size, neurons have to be connected across chip boundaries. We implement
these connections for BSS-2 using the EXTOLL networking technology. This
provides high bandwidths and low latencies, as well as high message rates.
Here, we describe the targeted pulse-routing implementation and required
extensions to the BSS-2 software stack. We as well demonstrate feed-forward
pulse-routing on BSS-2 using a scaled-down version without temporal merging.
