CompuServe Thread

Do you have a Pentium? Are you running Win3.1 or WFW3.11? You know, there is a problem w/ Intel's Pentium motherboard w/ the built-in 16550 UARTs that causes problems — there is a Windows fix for this (among other places, you can GO GATEWAY to find it), but apparently you're still screwed under DOS — something about clearing or not clearing the data buffer. I've got my external modem on an add-in I/O board, so I don't worry, although I sure could use that extra slot! Good luck. Dave

Doug, Each combination of hardware and software has it's own requirements and quirks. And the TAP config file lets you customize TAP to work with your hardware and the rotary (node) you will be making contact with. It doesn't take a lot of knowledge of communications to make the decisions in the config file as most of the selections are well documented within the file itself. But you do have to know a little about it and CIS. (Like you have to know that the carrier is the line speed or the speed of the connection between your modem and CIS's modem…eg..how fast you are talking to CIS. That the connect is the speed between your modem and your serial port… eg…..how fast your modem is talking to your computer….stuff like that.) The rest of it is going through your modem manual to see what you can change and why you would want to change it. But for the most parts, using the Hayes standards (or Hayes defaults) is the safe way to go as they have become almost the industry standards for all of this.

Hmm. I meant to mention that FIFO setting in my message to you, but forgot. If you set it on, but are not getting the message when you go online, then I'd say it's pretty likely that you don't have a 16550 UART — but should DEFINITELY get one. You can get a board from JDR Micro online in the MALL. It's product# MCT-AIO+ for $89.95 (1P/2S/1G) or they have an IDE/floppy/1P/2S/1G board (#MCT-IDEIO+) for $99.95 and a VLB version of the latter for $119.95 (#MCT-VIO+). Dave

Doug, If you have /FIFO=Y set in the TAP config file and you don't see the tap string about it actually being turned on, chances are you don't have a 16550 serial chip on the comm port. If you have an internal modem the comm port is part of the modem board, but if you have an external modem the comm port is part of the I/O board installed in the 'puter (or on the mo-bo). The only reason it's rather essential to have one of the faster serial port chips is that the 16450 chips that were used in the original ports is only reliable at speeds up to 9600 baud. (that's also the reason most plotters are limited to this comm speed too.) Now there were 16450 chips that would run reliably at speeds above this, but it was only a fluke. The spec on the chip only tests the chip at a maximum speed of 9600. The 16550 chip is tested at a maximum speed of 57,600 baud and should work reliably up to that speed. But to get it to do this, they have added a 16 bit buffer that is called the FIFO buffer. It stands for First In First Out. This gives the chip a little slack and prevents data loss at the higher speeds. But the buffer actually has to be initialized by the comm program that is using the serial port for it to work. The FIFO buffer isn't always active. This is to maintain compatability with programs and hardware that were made for use in the slower ports. The buffer can actually throw these for a loop and time them out. So you gotta initialize the buffer before you can use it. So that's why tap has the /FIFO=Y in the config file. The connect rate is also settable in the TAP config file, and essentially tells your hardware and software what data transfer rate you want between the modem and the serial port. It don't have anything to do with the phone line speed or data transfer rate. If you don't have a FIFO buffer, this munber shouldn't be any higher that 9600 baud. The &K4 enables software flow control. The &Q9 tells my PPI modem to conditionally use v42bis compression rather than MNP/5 (CIS doesn't support MNP/5…or at least they didn't) The S95=44 enables the CARRIER, COMPRESSION and PROTOCOL messages at logon. I've been thinking of changing this to 47 to get the error correction and actual line speed too.