121 #define MOTOR_ON	(ciab.prb &= ~DSKMOTOR)
122 #define MOTOR_OFF	(ciab.prb |= DSKMOTOR)
123 #define SELECT(mask)    (ciab.prb &= ~mask)
124 #define DESELECT(mask)  (ciab.prb |= mask)
276 	unsigned char prb = ~0;  in fd_select()  local
288 		prb &= ~DSKSIDE;  in fd_select()
290 		prb &= ~DSKMOTOR;  in fd_select()
291 	ciab.prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));  in fd_select()
292 	ciab.prb = prb;  in fd_select()
293 	prb &= ~SELMASK(drive);  in fd_select()
294 	ciab.prb = prb;  in fd_select()
300 	unsigned char prb;  in fd_deselect()  local
317 	prb = ciab.prb;  in fd_deselect()
318 	prb |= (SELMASK(0)|SELMASK(1)|SELMASK(2)|SELMASK(3));  in fd_deselect()
319 	ciab.prb = prb;  in fd_deselect()
403 	unsigned char prb;  in fd_calibrate()  local
411 	prb = ciab.prb;  in fd_calibrate()
412 	prb |= DSKSIDE;  in fd_calibrate()
413 	prb &= ~DSKDIREC;  in fd_calibrate()
414 	ciab.prb = prb;  in fd_calibrate()
418 		prb &= ~DSKSTEP;  in fd_calibrate()
419 		ciab.prb = prb;  in fd_calibrate()
420 		prb |= DSKSTEP;  in fd_calibrate()
422 		ciab.prb = prb;  in fd_calibrate()
426 	prb |= DSKDIREC;  in fd_calibrate()
429 		prb &= ~DSKSTEP;  in fd_calibrate()
430 		ciab.prb = prb;  in fd_calibrate()
431 		prb |= DSKSTEP;  in fd_calibrate()
433 		ciab.prb = prb;  in fd_calibrate()
455 	unsigned char prb;  in fd_seek()  local
478 	prb = ciab.prb;  in fd_seek()
479 	prb |= DSKSIDE | DSKDIREC;  in fd_seek()
481 		prb &= ~DSKSIDE;  in fd_seek()
484 		prb &= ~DSKDIREC;  in fd_seek()
486 	ciab.prb = prb;  in fd_seek()
496 		prb &= ~DSKSTEP;  in fd_seek()
497 		ciab.prb = prb;  in fd_seek()
498 		prb |= DSKSTEP;  in fd_seek()
500 		ciab.prb = prb;  in fd_seek()