Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!elroy.jpl.nasa.gov!ncar!typhoon.ucar.edu!mark From: mark@typhoon.ucar.edu (Mark Bradford) Newsgroups: comp.dcom.modems Subject: Re: Questions on High speed UARTS Message-ID: Date: 27 Nov 90 01:26:02 GMT References: <131@cf_su20.cf_su10.Sbi.COM> <6Dk8s3w163w@mudos.ann-arbor.mi.us> Sender: news@ncar.ucar.edu Reply-To: bradfrd2@ncar.ucar.edu (Mark Bradford) Organization: STORM Project Office, NCAR, Boulder Lines: 30 In <6Dk8s3w163w@mudos.ann-arbor.mi.us> mju@mudos.ann-arbor.mi.us (Marc Unangst) writes: >nee@cf_su14.Salomon.Com (Robert Nee) writes: >[Various questions about the 16550] >> P.S. the computer is a DELL 310 if that helps anyone... >As I recall, the Dell 310 has the serial ports built into the >motherboard -- which means it's unlikely it has anything even remotely >resembling an 8250, 16450, or 16550. More likely than not, it's got >some sort of VLSI chip that has the UARTs, the "glue" chips, and >everything else necessary for serial and parallel ports in it. You >aren't going to be able to replace this with a 16550, because you'd be >replacing your entire I/O subsystem, more or less. As a matter of fact, I've done just this upgrade on a Dell 310. It turns out that the 16C452 is a combination of 2 UARTs and a parallel port, and there >IS< a 16C552 that will replace it. (I got mine from Western Digital.) Caveat emptor -- I ran the 16550.EXE program I found on a local BBS to enable the FIFO buffers, and it claimed to work, but Kermit and Procomm Plus didn't really seem to know what to do with it. But just using the 16C552 instead of the 16C452 cured my dropped character problem, even without explicitly enabling the FIFOs. I have >heard< that Western Digital 16550As have some sort of problem that National Semiconductor 16550s don't, which may carry over to the 16C552, but this may be just rumor. Your mileage may vary. -- Mark Bradford (bradfrd2@ncar.ucar.edu) <> To err is human, to moo bovine.