rgcote@CLS.LCS.MIT.EDU.UUCP (03/03/87)
I am trying to find out whether a VAX can handle a synchronous 4.8 Kbit input line. We have either a VAX 750 running UNIX 4.2 BSD or a MicroVAX II/GPX also running UNIX 4.2 BSD. The line we will be using is a news wire service, similar to the AP news wire and will plug into either a DH or DZ panel (I think). We are trying to avoid using an IBM PC as a dedicated head to pre-process the line and buffer the the data stream before passing data to the VAX. Anyone out there have any useful information? Thanx. -Rob Cote P.S. Please e-mail response if at all possible, as I do not get to read this bulletin board too often. -- Rob Cote rgcote@cls.lcs.mit.edu (Internet) rgcote@mit-vax.UUCP
RGCOTE@XX.LCS.MIT.EDU.UUCP (03/04/87)
I am trying to find out whether a VAX can handle a synchronous 4.8 Kbit input line. We have either a VAX 750 running UNIX 4.2 BSD or a MicroVAX II/GPX also running UNIX 4.2 BSD. The line we will be using is a news wire service, similar to the AP news wire and will plug into either a DH or DZ panel (I think). We are trying to avoid using an IBM PC as a dedicated head to pre-process the line and buffer the the data stream before passing data to the VAX. Anyone out there have any useful information? Thanx. -Rob Cote P.S. Please e-mail response if at all possible, as I do not get to read this bulletin board too often. -- Rob Cote rgcote@cls.lcs.mit.edu (Internet) rgcote@mit-vax.UUCP -------
WITLICKI@WILLIAMS.BITNET.UUCP (03/04/87)
Rob Cote <RGCOTE@CLS.LCS.MIT.EDU> writes: >I am trying to find out whether a VAX can handle a synchronous 4.8 Kbit >input line. We have either a VAX 750 running UNIX 4.2 BSD or a MicroVAX >II/GPX also running UNIX 4.2 BSD. The line we will be using is a news >wire service, similar to the AP news wire and will plug into either a >DH or DZ panel (I think). We are trying to avoid using >an IBM PC as a dedicated head to pre-process the line and buffer the >the data stream before passing data to the VAX. Anyone out there >have any useful information? Thanx. A while back I was at a site where we wanted to read a 1200 baud news wire into a DEC 2060. There were about 40 or so 9600 baud terminals hardwired into the PDP 11/40 front end. During the midafternoon rush if N users did screen refreshes at once there was no way the front end could keep up with the news wire input. Since you can't poke a control-S at the news wire you *have* to be able to take all the characters as they come in or else throw them on the floor. What I ended up doing was taking an old 8K PDP 11/20 that was lying in the corner, added two serial ports, wrote about 150 lines of PDP/11 assembler and about 50 lines of Bliss code on the 2060 (which later grew as we processed headers). I'm sure a 750 or a uVax II can handle the 4.8 kbit line if that's all or almost all it's doing. How much other I/O can it do in addition to the news wire?... I've always had to experiment with this kind of thing. A dedicated front end may *have* to be your solution if you want to handle any sort of real interactive load. - randy