BIOS_TRAP
#define Bconstat(dev) toscallW(BIOS_TRAP, 1, (uint16)dev)
#define Bconin(dev) toscallW(BIOS_TRAP, 2, (uint16)dev)
#define Bconout(dev, chr) toscallWW(BIOS_TRAP, 3, (uint16)dev, (uint16)chr)
#define Rwabs(mode, buf, count, recno, dev, lrecno) toscallWPWWWL(BIOS_TRAP, 4, (int16)mode, (void *)buf, (int16)count, (int16)recno, (uint16)dev, (int32)lrecno)
#define Tickcal() toscallV(BIOS_TRAP, 6)
#define Getbpb(dev) (struct tos_bpb *)toscallW(BIOS_TRAP, 7, (uint16)dev)
#define Bcostat(dev) toscallW(BIOS_TRAP, 8, (uint16)dev)
#define Mediach(dev) toscallW(BIOS_TRAP, 9, (int16)dev)
#define Drvmap() (uint32)toscallV(BIOS_TRAP, 10)
#define Kbshift(mode) toscallW(BIOS_TRAP, 11, (uint16)mode)