Hi @Tim Edwards, I am running the

cace-gui

and when I hit the Simulate button, the debug output says that "Watchproc found nothing in the queue; will wait longer.". I wonder what went wrong? I am simulating the

sky130_ef_ip__instramp

of yours.

"Watchproc found nothing in the queue" is not actually an error; it's just a debug statement for figuring out issues related to multithreading. If the simulation is running correctly, then this message will be printed once or maybe twice per second until the simulation finishes. Currently I have an issue in CACE that if the simulation fails in certain ways, the simulation process might not exit, and CACE will get into a hung state. Leo Moser is working on a solution to this. It may be that you just have a long-running simulation, but watch the output for error messages from ngspice. You might want to choose single-threading from Settings until you're sure that the simulations all run and complete correctly.