Questa is an HDL simulator, intended as the successor to ModelSim. One big benefit of Questa over ModelSim is that it brings native 64-bit support, and the free edition has no line limits.
With coco-tb
coco-tb natively supports Questa. For Questa and ModelSim, we can specify SIM=questa or SIM=modelsim. We can also start both with the GUI (GUI=1).
Some notes:
- ModelSim requires a 32-bit installation of Python since it is itself a 32-bit software. For this reason, Questa is preferred over ModelSim, because it’s 64-bit and we don’t have to screw around with our Python install.
- coco-tb 1.9.1 introduced breaking Makefile changes for Questa. Version 1.9.0 is needed instead.