--- xinu/sys/kprintf.c	2018/04/24 17:39:04	1.1
+++ xinu/sys/kprintf.c	2018/04/24 17:40:13	1.1.1.2
@@ -1,88 +1,69 @@
-/* kprintf.c - kprintf, kputc, savestate, rststate */
+/* kprintf.c - kprintf, kputc--slightly edited from original Xinu */
 
 #include <conf.h>
 #include <kernel.h>
 #include <io.h>
-#include <slu.h>
 #include <tty.h>
-#include <procreg.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>
+#ifdef ATT7300
+int	slowtime = 500;
+/* Xinu console is the serial port on the back, assumed already
+   initialized by the downloading support */
+#else
+int     slowtime = 200;
+/* MECB console is the console MC6850, init'd by TUTOR */
+#endif
 
 /*------------------------------------------------------------------------
  *  kprintf  --  kernel printf: formatted, unbuffered output to CONSOLE
  *------------------------------------------------------------------------
  */
+
+/* kprintf is the routine to use for polling output, even in the case that */
+/* the calling program also uses SLU interrupts.  It shuts out interrupts */
+/* by going high-CPU-priority, saving the old CPU priority locally and */
+/* reestablishing it on return.  It varies from the original Vol I. Xinu */
+/* sources by not changing the device control register, but rather just */
+/* relying on high CPU priority to hold the console (did the original SLU */
+/* fail to post a transmit ready bit with interrupts enabled??) */
+
 kprintf(fmt, args)		/* Derived by Bob Brown, Purdue U.	*/
-        char *fmt;		/* Flow control added by Steve Munson	*/
+        char *fmt;
 {
-	int	kputc();
-	savestate();
-        _doprnt(fmt, &args, kputc, CONSOLE);
-        rststate();
-        return(OK);
+  static unsigned short savesr;
+  int     kputc();
+
+  _disable(&savesr);		/* orig. Xinu had "savestate()" */
+  _doprnt(fmt, &args, kputc, CONSOLE);
+  _restore(&savesr);		/* orig. Xinu had "rststate()" */
+  return(OK);
 }
 
 /*------------------------------------------------------------------------
- *  kputc  --  write a character on the non memory-mapped console device
- *		 using polled I/O
+ *  kputc  --  write a character on the console (or other SLU)
+ *  using polled I/O
  *------------------------------------------------------------------------
  */
-LOCAL	kputc(device ,c)
-	int	device;
-	register char c;	/* character to print from _doprnt	*/
+kputc(device,c)
+int device;
+register char c;	/* character to print from _doprnt	*/
 {
-	register int 	crstat, crbuf, ctstat;
-	register struct	tty	*ttyptr;
-
-	if ( device != CONSOLE || c == 0 )
+        struct csr *csrptr;
+/*T*/	int	slowdown;	/* added to delay output because host	*/
+/*T*/				/* can't take it at 9600 baud		*/
+	if ( c == 0 )
 		return;
 	if ( c == NEWLINE )
-		kputc( device, RETURN );
-	ttyptr = (struct tty *)devtab[device].dvioblk;	/* control block*/
-	if (ttyptr) {
-	   crstat = mfpr(RXCS); 			/* get recv. stat */
-	   crbuf = mfpr(RXDB); 		/* get content of receiver buffer */
-	   if ((crstat&SLUREADY) &&
-		(ttyptr->oheld || (ttyptr->oflow &&
-			(crbuf & SLUCHMASK) == ttyptr->ostop)))
-			do {
-			    crstat = mfpr(RXCS);	/* get recv stat */
-			    while (!(crstat&SLUREADY)) /* wait til ready */
-				    crstat = mfpr(RXCS);/* get recv stat */
-			    crbuf = mfpr(RXDB); 	/* get rec buffer */
-			} while ((crbuf&SLUCHMASK) == ttyptr->ostop);
-			ttyptr->oheld = FALSE;
-	   }
-	ctstat = mfpr(TXCS); /* get transmit status */
-	while (!(ctstat & SLUREADY)) /* not ready to transmit yet */
-		ctstat = mfpr(TXCS); /* poll for idle*/
-	mtpr(c & SLUCHMASK, TXDB); /* transmit character */
-	ctstat = mfpr(TXCS); /* get transmit status */
-	while (!(ctstat & SLUREADY))
-		ctstat = mfpr(TXCS); /* get transmit status */
-}
-
-LOCAL	int	savecrstat, savectstat;
-LOCAL	PStype	ps;
-/*------------------------------------------------------------------------------
- *  savestate  --  save the state of the non-memory mapped CONSOLE device
- *------------------------------------------------------------------------------
- */
-LOCAL	savestate()
-{
-	disable(ps);
-	savecrstat = mfpr(RXCS) & SLUENABLE;
-	savectstat = mfpr(TXCS) & SLUENABLE;
-	mtpr(SLUDISABLE, RXCS); 		/* disable receive intpts  */
-	mtpr(SLUDISABLE, TXCS);			/* disable transmit intpts */
-}
-
-/*--------------------------------------------------------------------------
- *  rststate  --  restore the state of the non-memory mapped CONSOLE device
- *--------------------------------------------------------------------------
- */
-LOCAL	rststate()
-{
-	mtpr(savecrstat, RXCS);
-	mtpr(savectstat, TXCS);
-	restore(ps);
+		kputc(device, RETURN );
+	csrptr = (struct csr *)devtab[device].dvcsr;
+	while ( (csrptr->cstat & SLUTRANSREADY) == 0 ) ;  /* poll for idle*/
+	csrptr->cbuf = c;
+/*T*/	for(slowdown=0;slowdown<slowtime;slowdown++) ;
+	while ( (csrptr->cstat & SLUTRANSREADY) == 0 ) ;  /* poll for idle*/
 }