8 Simulation

8.4 GTKWave simulator

Although it remains almost entirely hidden for the average user, the simulator is essentially an electronic design software. It produces an ’ObjectName.vcd’ file that, correspondingly, can be analyzed using the tools of electronic design. One of the popular tools is GTKWave. The contents of the .vcd file can be displayed as shown in 8.1. (To reproduce the figure, one has to switch the signal forms to ’analog stepwise’ and ’analog interpolated’, respectively, and increase the ’insert analog height extension’ to the single-text line annotation.)

Refer to caption
Figure 8.1: The summary of AP generation as seen in the simulator. The information is essentially the same that in Figure 3.15 (for codename ’0’, i.e., ’Simple delivery’). The rush-in current produces its voltage time derivative, the resulting voltage time derivative generates the neuron’s output voltage, the AP. The neuron passes (due to the excitation) from stage ’Relaxing’ (codename ’1’) to ’Computing’ (codename ’2’) and ’Delivering’ (codename ’2’) as described above.