/* * TJU16 tape driver */#include <sys/param.h>#include <sys/inode.h>#include "saio.h"struct	device{	int	htcs1;	int	htwc;	caddr_t	htba;	int	htfc;	int	htcs2;	int	htds;	int	hter;	int	htas;	int	htck;	int	htdb;	int	htmr;	int	htdt;	int	htsn;	int	httc;	int	htbae;	/* 11/70 bus extension */	int	htcs3;};#define	HTADDR	((struct device *)0172440)#define	GO	01#define	WCOM	060#define	RCOM	070#define	NOP	0#define	WEOF	026#define	SFORW	030#define	SREV	032#define	ERASE	024#define	REW	06#define	DCLR	010#define CLR	040#define P800	01300		/* 800 + pdp11 mode */#define	P1600	02300		/* 1600 + pdp11 mode */#define	IENABLE	0100#define	RDY	0200#define	TM	04#define	DRY	0200#define EOT	02000#define CS	02000#define COR	0100000#define PES	040#define WRL	04000#define MOL	010000#define PIP	020000#define ERR	040000#define FCE	01000#define	TRE	040000#define HARD	064023	/* UNS|OPI|NEF|FMT|RMR|ILR|ILF */#define	SIO	1#define	SSFOR	2#define	SSREV	3#define SRETRY	4#define SCOM	5#define SOK	6htopen(io)register struct iob *io;{	register skip;int i;	htstrategy(io, REW);	skip = io->i_boff;	while (skip--) {		io->i_cc = -1;		while (htstrategy(io, SFORW))			;		i = 0;		while (--i)			;		htstrategy(io, NOP);	}}htclose(io)register struct iob *io;{	htstrategy(io, REW);}htstrategy(io, func)register struct iob *io;{	register unit, den, errcnt;	unit = io->i_unit;	errcnt = 0;retry:	HTADDR->htcs2 = unit&03;	if(unit > 3)		den = P1600;	else		den = P800;	htquiet();	if((HTADDR->httc&03777) != den)		HTADDR->httc = den;	HTADDR->htba = io->i_ma;	HTADDR->htfc = -io->i_cc;	HTADDR->htwc = -(io->i_cc>>1);	den = ((segflag) << 8) | GO;	if (func == READ)		den =| RCOM;	else if (func == WRITE)		den =| WCOM;	else if (func == SREV) {		HTADDR->htfc = -1;		HTADDR->htcs1 = den | SREV;		return(0);	} else		den |= func;	HTADDR->htcs1 = den;	while ((HTADDR->htcs1&RDY) == 0)		;	if (HTADDR->htds&TM) {		htinit();		return(0);	}	if (HTADDR->htcs1&TRE) {		if (errcnt == 0)			printf("tape error: cs2=%o, er=%o",			    HTADDR->htcs2, HTADDR->hter);		htinit();		if (errcnt == 10) {			printf("\n");			return(-1);		}		errcnt++;		htstrategy(io, SREV);		goto retry;	}	if (errcnt)		printf(" recovered by retry\n");	return(io->i_cc+HTADDR->htfc);}htinit(){	int omt, ocs2;	omt = HTADDR->httc & 03777;	ocs2 = HTADDR->htcs2 & 07;	HTADDR->htcs2 = CLR;	HTADDR->htcs2 = ocs2;	HTADDR->httc = omt;	HTADDR->htcs1 = DCLR|GO;}htquiet(){	while ((HTADDR->htcs1&RDY) == 0)		;	while (HTADDR->htds&PIP)		;}