4.3BSD - /usr/src/sys/mdec/tmtoggle.s

   1: /*
   2:  * Copyright (c) 1980, 1986 Regents of the University of California.
   3:  * All rights reserved.  The Berkeley software License Agreement
   4:  * specifies the terms and conditions for redistribution.
   5:  */
   6: 
   7: #ifndef lint
   8: _sccsid:.asciz  "@(#)tmtoggle.s	7.1 (Berkeley) 6/5/86"
   9: #endif not lint
  10: 
  11: /*
  12:  * Prototype toggle in bootstrap code for tm type tapes.
  13:  * If on anything but a 780 with the drive on uba0
  14:  * this will have to be repaired by patching uba and umem.
  15:  */
  16: begin:
  17:         movl    uba,r1
  18:         movl    $0x80200000,0x800(r1)
  19:         clrl    0x804(r1)
  20:         movl    umem,r2
  21:         bisl2   $0172520,r2
  22:         mnegw   $512,4(r2)
  23:         clrw    6(r2)
  24:         movw    $03,2(r2)
  25:         halt
  26:         .align  2
  27: uba:    .long   0x20006000
  28: umem:   .long   0x2013e000

Defined functions