> For the complete documentation index, see [llms.txt](https://elishai.gitbook.io/retinal-stimulation-modeling-environment/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://elishai.gitbook.io/retinal-stimulation-modeling-environment/sac-plexus-model/before-we-begin.md).

# Before we begin

NEURON is using .mod files to specify channels and dynamics. You can read about .mod files and how they are created and specified in:

{% embed url="<https://www.neuron.yale.edu/neuron/static/py_doc/modelspec/programmatic/mechanisms/nmodl.html>" %}

RSME is using various membrane mechanisms. One of them is GradSyn, which we used to model SAC-SAC synapses. You can download RSME's .mod files in:

{% file src="/files/3M0rJeAc25cmy2yOsdYg" %}

Unzip the mods directory to your project folder. Now you will have to compile the files to work with NEURON. To do so, go to the Terminal, get into your project folder, and enter:

```
nrnivmodl \mods
```

It will create a new folder (in Mac in will be x86\_64), in which the compiled C files.

{% hint style="warning" %}
Compiling these files is important. You will not be able to proceed with this example without it.
{% endhint %}