--- xinu/sys/ttywrite.c	2018/04/24 17:39:04	1.1
+++ xinu/sys/ttywrite.c	2018/04/24 17:40:00	1.1.1.2
@@ -4,32 +4,40 @@
 #include <kernel.h>
 #include <tty.h>
 #include <io.h>
-#include <slu.h>
+/* set up macros for appropriate SLU as spec. by SLUCHIP:
+   if SLUCHIP==6850, #include slu6850.h, #define TTYWRITE ttywrite6850, etc.
+   if SLUCHIP==7201, #include slu7201.h, #define TTYWRITE ttywrite7201, etc.
+   if SLUCHIP undef.,#include slu.h, #define TTYWRITE ttywrite  (orig. case)
+   similarly sluaccess.h, other TTY fns */
+#include <sluinclude.h>
 
 /*------------------------------------------------------------------------
  *  ttywrite - write one or more characters to a tty device
  *------------------------------------------------------------------------
  */
-ttywrite(devptr, buff, count)
-struct	devsw	*devptr;
-char	*buff;
-int	count;
+TTYWRITE(devptr,buff,count)
+	register struct	devsw	*devptr;
+	register char	*buff;
+	register int	count;
 {
+	register struct csr *cptr;
 	register struct tty *ttyp;
-	int ncopied;
-	PStype ps;
+	int avail;
 
-	if (count < 0)
-		return(SYSERR);
-	if (count == 0)
-		return(OK);
-	disable(ps);
 	ttyp = &tty[devptr->dvminor];
-	count -= (ncopied = writcopy(buff, ttyp, count));
-	buff += ncopied;
-	for ( ; count>0 ; count--)
-		ttyputc(devptr, *buff++);
-	restore(ps);
+	cptr = (struct csr *)devptr->dvcsr;
+
+	disable();
+	if ( (avail=scount(ttyp->osem)) > count) {
+		writcopy(buff, ttyp, count);
+	} else {
+		writcopy(buff, ttyp, avail);
+		buff += avail;
+		for (count-=avail ; count>0 ; count--)
+			TTYPUTC(devptr, *buff++);
+	}
+	slutenable(cptr); /* enable transmitter ints */
+	restore();
 	return(OK);
 }
 
@@ -38,31 +46,20 @@ int	count;
  *------------------------------------------------------------------------
  */
 LOCAL writcopy(buff, ttyp, count)
-char	*buff;
-struct	tty *ttyp;
-int	count;
+	register char	*buff;
+	register struct	tty *ttyp;
+	register int	count;
 {
-	register int	avail;
-	register char	*cp, *qhead, *qend, *uend;
+	register char	*qhead, *qend, *uend;
 
-	avail = scount(ttyp->osem);
 	qhead = &ttyp->obuff[ttyp->ohead];
 	qend  = &ttyp->obuff[OBUFLEN];
-	cp    = buff;
 	uend  = buff + count;
-	while (avail-- > 1 && cp < uend) {
-		if (*cp == NEWLINE && ttyp->ocrlf) {
-			*qhead++ = RETURN;
-			--avail;
-			if ( qhead >= qend )
-				qhead = ttyp->obuff;
-		}
-		*qhead++ = *cp++;
+	while (buff < uend) {
+		*qhead++ = *buff++;
 		if ( qhead >= qend )
 			qhead = ttyp->obuff;
-	}					/* avail decremented one*/
-	ttyp->ohead = qhead - ttyp->obuff;	/* extra time when loop	*/
-	sreset(ttyp->osem, ++avail);		/* condition fails.	*/
-	(ttyp->ioaddr)->ctstat = SLUENABLE;
-	return(cp - buff);
+	}
+	ttyp->ohead = qhead - ttyp->obuff;
+	sreset(ttyp->osem, scount(ttyp->osem)-count);
 }