Research V5 development

[unix-history] / usr / sys / dmr / vs.c

#
/*
*      Copyright 1973 Bell Telephone Laboratories Inc
*/

/*
* Screw Works interface via DC-11
*/

#include "../tty.h"

#define VSADDR  0174150
#define CDLEAD  01
#define B1200   030
#define STOP1   0400
#define CLSEND  02
#define RQSEND  01

#define MAGIC_MAP 0377

struct {
       int     vsrcsr;
       int     vsrbuf;
       int     vsxcsr;
       int     vsxbuf;
};

struct {
       struct  clist   iq;
       struct  clist   oq;
} vs;

char    vsmap[] "?0*#?546?213?879?";

vsopen(dev)
{
       VSADDR->vsrcsr = IENABLE|B1200|CDLEAD;
       VSADDR->vsxcsr = STOP1|IENABLE|B1200;
       vschar(0);
}

vsclose(dev)
{
       VSADDR->vsrcsr =& ~IENABLE;
       while (getc(&vs.iq) >= 0);
}

vswrite(dev)
{
       register int count, c;

       count = 0;
       while ((c=cpass()) >= 0) {
               if (--count <= 0) {
                       count = 60;
                       vschar(0);
               }
               vschar(c);
       }
       vschar(0);
}

vschar(c)
{

       c =^ MAGIC_MAP;
       spl5();
       while (vs.oq.c_cc > 60) {
               vsxintr();
               sleep(&vs.oq, TTIPRI);
       }
       putc(c, &vs.oq);
       vsxintr();
       spl0();
}

vsxintr()
{
       static lchar;
       register c;
       register int *xcsr;

       xcsr = &VSADDR->vsxcsr;
       if (*xcsr&DONE) {
               if (lchar==MAGIC_MAP) {
                       *xcsr =& ~RQSEND;
                       lchar = 0;
                       if (vs.oq.c_cc==0)
                               goto wake;
               }
               if ((*xcsr&CLSEND) == 0) {
                       *xcsr =& ~RQSEND;
                       *xcsr =| RQSEND;
                       if ((*xcsr&CLSEND) == 0)
                               goto wake;
               }
               if ((c = getc(&vs.oq)) >= 0)
                       VSADDR->vsxbuf = lchar = c;
               if (vs.oq.c_cc <= 15)
           wake:
                       wakeup(&vs.oq);
       }
}

vsread(dev)
{
       register int c;

       spl5();
       while ((c = getc(&vs.iq)) < 0)
               sleep(&vs.iq, TTIPRI);
       spl0();
       passc(vsmap[c&017]);
}

vsrintr()
{
       register int c;

       c = VSADDR->vsrbuf;
       if (vs.iq.c_cc<=10)
               putc(c, &vs.iq);
       wakeup(&vs.iq);
}