xref: /csrg-svn/sys/vax/mdec/httoggle.s (revision 23144)
1*23144Smckusick/*
2*23144Smckusick * Copyright (c) 1980 Regents of the University of California.
3*23144Smckusick * All rights reserved.  The Berkeley software License Agreement
4*23144Smckusick * specifies the terms and conditions for redistribution.
5*23144Smckusick */
611091Ssam
7*23144Smckusick#ifndef lint
8*23144Smckusick_sccsid:.asciz	"@(#)httoggle.s	6.2 (Berkeley) 06/08/85"
9*23144Smckusick#endif not lint
10*23144Smckusick
11*23144Smckusick
1211091Ssam/*
1311091Ssam * Prototype toggle in bootstrap code for ht type tapes.
1411091Ssam * If on anything but a 780 with a tape at slave 1 of mba 1
1511091Ssam * this will have to be repaired by patching mba and ht.
1611091Ssam */
1711091Ssam	movl	mba,r10
1811091Ssam	mull3	ht,$0x80,r11
1911091Ssam	addl3	r11,r10,r11
2011091Ssam	addl2	$0x400,r11
2111091Ssam	movl	$1,4(r10)
2211091Ssam	movl	$9,(r11)
2311091Ssam	cvtwl	$012300,0x24(r11)
2411091Ssam	clrl	12(r10)
2511091Ssam	movl	$0x80000000,0x800(r10)
2611091Ssam	cvtwl	$-512,16(r10)
2711091Ssam	movl	$0x39,(r11)
2811091Ssam	halt
2911091Ssam	.align	2
3011091Ssammba:	.long	0x20012000
3111091Ssamht:	.long	0
32