SCPE_NXREG 3665 src/simh/scp.c return SCPE_NXREG; SCPE_NXREG 6728 src/simh/scp.c return SCPE_NXREG; SCPE_NXREG 6744 src/simh/scp.c return SCPE_NXREG;