Nsys/sys/nsys/dmr/vs.c
#
/*
* Screw Works interface via DC-11
*/
#include "/sys/nsys/tty.h"
#define VSADDR 0174150
#define CDLEAD 01
#define B1200 030
#define STOP1 0400
#define CLSEND 02
#define RQSEND 01
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);
while (getc(&vs.oq) >= 0);
}
vswrite(dev)
{
int count, c;
count = 0;
while (cpass(&c) >= 0) {
if (--count <= 0) {
count = 60;
vschar(0);
}
vschar(c);
}
vschar(0);
}
vschar(c)
{
c =^ 0277; /* 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==0277) {
*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);
}