xref: /original-bsd/sys/vax/mdec/uttoggle.s (revision 92d3de31)
1/*	uttoggle.s	4.3	83/03/06	*/
2
3/*
4 * Prototype toggle in bootstrap code for ut type tapes.
5 * If on anything but a 780 with the drive on uba0
6 * this will have to be repaired by patching uba and umem.
7 */
8begin:
9	movl	uba,r1
10	movl	$0x80200000,0x800(r1)
11	clrl	0x804(r1)
12	movl	umem,r2
13	bisl2	$0172440,r2
14	movw	$0x04c0,26(r2)		/* set tape density & format */
15	mnegw	$512,6(r2)		/* set frame count */
16	mnegw	$256,2(r2)		/* set word count */
17	clrw	4(r2)			/* set bus address */
18	movw	$0x39,(r2)		/* set command and go */
19	halt
20	.align	2
21uba:	.long	0x20006000
22umem:	.long	0x2013e000
23