[net.unix-wizards] Vadic VA811 dialer with 4.1BSD

bobvan (07/02/82)

Experiences using the Vadic VA811 dialer with 4.1BSD UNIX:

Don't be afraid to remove code from dnd.c if your dialer hangs after
dialing a busy number.  You probably have the "new" dialer prom that
sends only one char on timeout instead of four as the "old" prom did.
Apparently, Berkeley is still using the old prom and this code is there
as a band-aid.  A diff -c showing the removed code follows (line numbers
will be wrong as I have made other mods.)

Also note that the automatic dial mode select feature may cause flakey
operation with some PBX's and CO's.  If either is slow in breaking dial
tone after the first digit dialed, the dialer will assume pulse mode
and end up dialing the first digit twice (once in tone mode and once
in pulse mode.)  If your PBX and CO can accept tone dialing, select
this by setting A3 off and A4 on, otherwise select pulse dialing with
A3 and A4 off.

I would like to gratefully acknowledge the help of Jim Constantine
at Philips labs who had similar problems and verified my results.

				Bob Van Valzah
				(...!decvax!ittvax!tpdcvax!bobvan)

*** dnd.orig.c	Thu May 27 14:28:14 1982
--- dnd.c	Thu Jul  1 13:43:12 1982
***************
*** 346,352
  	if(read(fd,&c,1)!=1) c = 'M';
  	if(c=='B'||c=='G') {
  		pc(ABORT);
! 		read(fd,&cc,1);
  	}
      out:
  	close(fd);

--- 349,356 -----
  	if(read(fd,&c,1)!=1) c = 'M';
  	if(c=='B'||c=='G') {
  		pc(ABORT);
! 		/* RAV dialing a busy nunber hangs at this read */
! 		/*read(fd,&cc,1);*/
  	}
      out:
  	close(fd);
***************