From: Jae Chung (eclipse!
Date: Thu Jul 30 1992 - 19:00:14 CDT

****** my original post

> Hi Sun Managers;
> Currently, I have SunOS 4.0.3 running on 4/370 w/ ALM board.
> One of EPSON printers is attached to one of ALM board, and its
> cable length (between printer and ALM board) is roughly 200 ft.
> It only uses Pin 2,3 & 7 and do Software flow control (XON, XOFF).
> It works fine about 8 hrs and it starts sucking up all the CPU
> power (100 %) until turn off the EPSON printer for couple of
> hours and turn it back on.....
> It works w/o problems w/ using 25 ft cables for long long time...
> I'm suspecting that impetence is building on its cable after
> for a while...
> Question:
> Is there anybody has same situation like this?
> Or anybody knows how to fix this problem?
> J. Chung

I got few responses from

Thanks to all who responded... Forgive me I missed anyone's name

Here is the summary...........

1. RS232 can be used w/ cable length up to 50 ft by the spec.
2. Cable length cab be extended if you use two RS-232<==>RS-422 converters.
   (Try with RS232 cables first, and if it does not work, you can adopt this
3. For long distance, use the heaviest gauge of wire (like 22 gauge)
4. Use shielded wire.
5. Connect the shield to one end only, if the shield is connected at both ends.
6. For SunOS version 4.0.3, apply patch no. 100020-04 to fix i/o streams hang
   w/ framing errors....

                                                        J. Chung

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