Decade counter (74LS68) simulation error

Schematic Simulation (Ngspice)
1

Hi guys, I’m quite new to KiCad, and I’m trying to simulate a 74LS68 decade counter powered by a 555 timer running on 10Hz. For some reason the simulation results in an error, but it runs when the decade counter is removed(there are still some weird voltage peaks at the output of 555timer). How can I simulate the decade counter without errors?

Error message:

Dot command ‘.probe alli’ and digital nodes are not compatible.
Evtcheck_nodes: Auto bridging is switched off but node net-u3-q is mixed-type.
Error: circuit not parsed.
Error: vector time not found!
Error: vector time not found!
Error: vector time not found!

Tick boxes of ‘Save all currents’ and ‘Save all power dissipations’ are both unchecked.
Model used for 74LS68 is from “74xx-models.7z” in https://ngspice.sourceforge.io/modelparams.html

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2

Dot command ‘.probe alli’ and digital nodes are not compatible.
is a direct reaction to ‘Save all currents’ being checked.

So the info change has not been aknowledged in Eeschema.

Save the workbook, exit Eeschema, and open Eeschema again and then run the simulation.

To simplify the project, in a first attempt you might remove the 555 and use a VPULSE source as input to the counter.

To run the logic devices at 5V, you have to put a .param vcc=5 into a textbox on the Eeschema canvas. Otherwise they will run at 3.3V.

3

After exiting and re-entering the entire software, the error is gone and it runs! Thanks, much appreciated.

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