For the Z80-based RC2014 only, end simulation if a halt instruction is executed with interrupts disabled.
The RC2014 doesn't currently support non-maskable interrupts; if that happens in the future, this might need to be changed to a different mechanism, as EtchedPixels described in pull request https://github.com/EtchedPixels/RC2014/pull/31.
For the Z80-based RC2014 only, end simulation if a halt instruction is executed with interrupts disabled. The RC2014 doesn't currently support non-maskable interrupts; if that happens in the future, this might need to be changed to a different mechanism, as EtchedPixels described in pull request https://github.com/EtchedPixels/RC2014/pull/31.