Exchange pyNN brain with nest brain [solved]


Dear All,

I created a complete simulation with the NRP 2.3 including a robot called spikebot, a world called
four_obstacles and a lot of transfer functions. Right now I am trying to exchange the pyNN.nest brain with a pure nest brain since I want to use a new neuron model which I have already
implemented in nest. This seems the easiest way for me to get results soon.
In the current simulation the transfer function grab_events receives events from the DVS module implemented in the NRP and creates a spike source “input_neurons” which maps the events onto the brain population nrp.brain.sensors. Since I modified the neuron populations from pyNNest models to nest models the mapping doesn’t seem to work anymore. The function grab_events returns me the ERROR “‘int’ object is not iterable” but I don’t understand why the transfer function receives an int object instead of a list and what I have
to change.

I would be very grateful if you could try out both simulations. I appended them as zip files. should work without problems while doesn’t
work at all. It might be that you have to add the dvs plugin to your NRP install before any of the two
simulation works, which can be found here:

I would very greatful for any help since I’ve been working on this for a few month and would
be very glad to see results soon.

I renamed the files to txt since zip is not allowed. The txt ending has to be removed (1.7 MB) (1.7 MB)

Thank you very much and best regards,
Thorben Schoepe

Research Assistant and PhD student at
Neuromorphic Behaving Systems group
Technical Faculty, Bielefeld University


Dear Thorben,

Please note that you can use almost any NEST model within PyNN using the native_cell_type() function - see - so it is not generally necessary to rewrite the entire model with PyNEST.

Hope this helps,



Dear Andrew,

I just found the ERROR.
I had to add the type directnest simulation
into the bibi_configuration file. Now it’s working
with the nest code.

Thank you for the fast response,