123146Smckusick/* 2*29324Smckusick * Copyright (c) 1980, 1986 Regents of the University of California. 323146Smckusick * All rights reserved. The Berkeley software License Agreement 423146Smckusick * specifies the terms and conditions for redistribution. 523146Smckusick */ 611093Ssam 723146Smckusick#ifndef lint 8*29324Smckusick_sccsid:.asciz "@(#)mttoggle.s 7.1 (Berkeley) 06/05/86" 923146Smckusick#endif not lint 1023146Smckusick 1111093Ssam/* 1211093Ssam * Prototype toggle in bootstrap code for mt type tapes. 1311093Ssam * If on anything but a 780 with a tape at drive 0 of mba 1 1411093Ssam * this will have to be repaired by patching mba and mt. 1511093Ssam */ 1611093Ssam movl mba,r10 1711093Ssam mull3 mt,$0x80,r11 1811093Ssam addl3 r11,r10,r11 1911093Ssam addl2 $0x400,r11 2011093Ssam movzbl $1,4(r10) 2111093Ssam movzbl $4,8(r11) /* drive zero, one record */ 2211093Ssam clrl 12(r10) /* set address to zero */ 2311093Ssam movl $0x80000000,0x800(r10) /* validate map register */ 2411093Ssam cvtwl $-512,16(r10) /* set byte count */ 2511093Ssam movzwl $512,20(r11) /* set byte count */ 2611093Ssam0: 2711093Ssam movl 0x44(r11),r0 2811093Ssam bbc $15,r0,0b 2911093Ssam movzbl $071,(r11) /* read forward, go */ 3011093Ssam halt 3111093Ssam .align 2 3211093Ssammba: .long 0x20012000 3311093Ssammt: .long 0 34