Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!swrinde!cs.utexas.edu!uunet!sparky!dsndata!jeff From: jeff@dsndata.uucp (Jeff Minnig) Newsgroups: comp.sys.hp Subject: Re: Asynch Port on HP9000 345 Message-ID: Date: 19 Mar 91 14:06:26 GMT References: <1991Mar18.162849.27463@cuff.uucp> Sender: jeff@dsndata.UUCP Organization: Design Data Lines: 59 In-reply-to: vic@cuff.uucp's message of 18 Mar 91 16:28:49 GMT In article <1991Mar18.162849.27463@cuff.uucp> vic@cuff.uucp (Victor Berry) writes: > > This interface has no problem in the outward direction. We could talk out > at 9600 all day long. The difficulty lies in incoming data. It will and > does lose data at speeds above 2400. We actually run it at 4800 but it > times out frequently. > > My question is: > -------------- > > Does anyone out there in netland know of a way to speed this port up? > Sorry, there is no patch for the 98626. I believe you problem lies in the fact that the 98626 has only a 1 byte I/O buffer on the card. When the data rate gets too high, kernel<->card link simply loses chars and becomes unusable. We have seen this type of behavior both from the 98626 and the 98644 cards, both of which only have a 1 byte buffer. My recommendation is to replace the 98626 card with a 98642A MUX card. The 98642A MUX card has a 128 byte input buffer and a 16 byte output buffer on the card. We have run everything from a Hayes 1200 to a Telebit T2500 @ 19200 baud on a 98642A card with no data problems. The 98642A card specs like this: Electrical Interface: IEA $S232C, CCITT V.28 Number of ports: 4 (1 modem, 3 direct-connect) Data rates: 110 to 19200 I/O Buffer Size: 128/16 bytes per port Character Size: 7 or 8 bits Parity: Odd, Even, or None Stop Bits: 1 or 2 (6..8 bits/char) Hardware Handshake: Provided by HP-UX per tty(4) Software Handshake: Provided by HP-UX per tty(4) Interrupt level: 3..6 (default of 3) Aggregte MUX thourghtput is card-limited to 76800 bps continuous input data. -jeff- -- ---------------------------------------------------------------------- I said it, not the people I work for. ---------------------------------------------------------------------- Jeff Minnig | (402) 476-8278 Design Data | 1033 'O' St. Suite 324 | {hpfcla,sparky,unocss}!dsndata!jeff Lincoln NE 68508 | ---------------------------------------------------------------------- Home is where your keyboard is. ----------------------------------------------------------------------