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- Path: sparky!uunet!psinntp!colornet!dfilip
- From: dfilip@colornet.com
- Newsgroups: comp.os.coherent
- Subject: Re: Loosing chars with ZyXEL 1496E+ and Coherent 4.0.1
- Keywords: modem 19200
- Message-ID: <73@colornet.com>
- Date: 2 Jan 93 15:36:44 GMT
- References: <1993Jan02.043138.6691@acme.gen.nz>
- Distribution: world
- Summary: Using a modmem at 19200
- Organization: ColorNet Information Systems
- Lines: 40
-
- Craig Harding writes:
- >kosta@blues.kk.sub.org (Kosta Kostis) writes:
- >> I'm running Coherent 4.0.1 on a i386SX/16 with 2 MB and a ZxXEL 1496E+
- >> having real trouble connecting them. I have never faced these problems
- >> with my old Hyundai 2400 bps internal modem. The ZyXEL 1496E+ is
- >> connected to a multi I/O card with 16450 UARTs, so I thought, I'd better
- >> run at no more than 19200 bps. I use device "/dev/com1fr" for the modem.
- >>
- >> Characters get lost between the PC and the modem. "at&t8" shows clearly,
- >> that characters get lost, so using another UUCP suite like Taylor won't
- >> help (much). I guess there's some trouble with my device driver. :-(
- >
- >I think the basic problem is that your machine isn't fast enough to handle the
- >port at 19200, even though it's using hardware flow control. I suspect some
- >flaw somewhere means that incoming character overruns can still happen despite
- >using RTS/CTS signalling, although I'm just speculating based on my
- >(low) expectations of PC hardware and the software that runs on it. I use a
- >U-1496E on a 16Mhz 386SX but the serial port in question has a 16550 on it.
- >You need to either get one of those or slow down your modem (probably
- >dramatically).
-
- Because I've heard people state that you need at 16550 to run at 19200, I
- thought I'd mention that I am running a TwinCom 14400/V42bis at 19200 with
- a 16450 (no buffering), and very rarely do I get any UUCP errors (receive
- about 1MB in news traffic a day). However, I have a 386/33 w/64K cache, which
- might make a difference over a 386/16. The point is that it appears as though
- the 16550 is only required for >9600 on slower machines.
-
- Regards,
-
- Dave.
-
- --
- =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
- = David E. Filip UUCP : dfilip@colornet.com =
- = ColorNet Information Systems CIS : 76430,3111 =
- =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
- = If David Cutler had been a heavy drug user in the 60's, he probably =
- = would have written Unix instead ... =
- =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
-