SCPE_NXREG 3785 src/simh/scp.c return SCPE_NXREG; SCPE_NXREG 6845 src/simh/scp.c return SCPE_NXREG; SCPE_NXREG 6861 src/simh/scp.c return SCPE_NXREG;