240 #define MOTOR_ON	(ciab.prb &= ~DSKMOTOR)
241 #define MOTOR_OFF	(ciab.prb |= DSKMOTOR)
242 #define SELECT(mask)    (ciab.prb &= ~mask)
243 #define DESELECT(mask)  (ciab.prb |= mask)
395 	unsigned char prb = ~0;  in fd_select()  local
407 		prb &= ~DSKSIDE;  in fd_select()
409 		prb &= ~DSKMOTOR;  in fd_select()
410 	ciab.prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));  in fd_select()
411 	ciab.prb = prb;  in fd_select()
412 	prb &= ~SELMASK(drive);  in fd_select()
413 	ciab.prb = prb;  in fd_select()
419 	unsigned char prb;  in fd_deselect()  local
436 	prb = ciab.prb;  in fd_deselect()
437 	prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));  in fd_deselect()
438 	ciab.prb = prb;  in fd_deselect()
516 	unsigned char prb;  in fd_calibrate()  local
524 	prb = ciab.prb;  in fd_calibrate()
525 	prb |= DSKSIDE;  in fd_calibrate()
526 	prb &= ~DSKDIREC;  in fd_calibrate()
527 	ciab.prb = prb;  in fd_calibrate()
531 		prb &= ~DSKSTEP;  in fd_calibrate()
532 		ciab.prb = prb;  in fd_calibrate()
533 		prb |= DSKSTEP;  in fd_calibrate()
535 		ciab.prb = prb;  in fd_calibrate()
539 	prb |= DSKDIREC;  in fd_calibrate()
542 		prb &= ~DSKSTEP;  in fd_calibrate()
543 		ciab.prb = prb;  in fd_calibrate()
544 		prb |= DSKSTEP;  in fd_calibrate()
546 		ciab.prb = prb;  in fd_calibrate()
568 	unsigned char prb;  in fd_seek()  local
591 	prb = ciab.prb;  in fd_seek()
592 	prb |= DSKSIDE | DSKDIREC;  in fd_seek()
594 		prb &= ~DSKSIDE;  in fd_seek()
597 		prb &= ~DSKDIREC;  in fd_seek()
599 	ciab.prb = prb;  in fd_seek()
609 		prb &= ~DSKSTEP;  in fd_seek()
610 		ciab.prb = prb;  in fd_seek()
611 		prb |= DSKSTEP;  in fd_seek()
613 		ciab.prb = prb;  in fd_seek()