How to use com ports 5-8?

How to use com ports 5-8?

Post by Zachary Sigma Vonl » Tue, 16 Jul 1996 04:00:00

I recently added a new I/O card to my system that has 4 serial ports (via 2
16552 UARTS) that are each configurable from com 1-8.  Right now, I have
the first three ports set to com 1, 3, and 4 (the modem is on 2).  All of
those ports work fine.  However, I can't get the fourth port (on com 5) to
work right.  The board's documentation says that it maps com5 to 0x2F0 (I
assume this is standard?) so I use this line in /etc/rc.d/rc.serial:
setserial -b /dev/cua4 port 0x2F0 uart 16550A irq 15

Looking through linux/drivers/char/serial.c I noticed this line:
{ 0, BASE_BAUD, 0x1A0, 9, FOURPORT_FLAGS },  /* ttyS4 */

Which is probably why when the setserial -bg command for cua4 is
issued, I get this output:
/dev/cua4 at 0x02f0 (irq = 15) is a 16550 (Fourport)

Since I am trying to use this port to connect to my calculator (HP48) I use
the program rx/sx to test the connection.  Neither works.  However, if I do
a cat /dev/cua4, then attempt to start a transfer from the calculator, I
see what looks like the calculator's attempt to start a transfer get
printed out.

I tried switching around the port address/irqs to see if the card was the
problem - it isn't.  No matter where I locate /dev/cua4, I can't get it to
work right.  Does the fact that setserial thinks it is a fourport have
something to do with this?

Is there any way that I can modify the serial driver to treat com ports 5-8
just like the first four?

Zachary X. Vonler -----------------------------

The world's as ugly as sin,
And almost as delightful
                -- Frederick Locker-Lampson


1. COM-T redirects COM port to telnet connection


Has anyone ever used this? I'm looking for it.

I last saw it in the days of Win 3.1 and Trumpet Winsock.

Basically it redirected COMX to a telnet connection.

I'm looking for a WIN95 solution.

All comments and suggestions welcome.

Alternatively anything else that will allow WIN9X clients to access a modem on
a FreeBSD Unix box would be great.

Irvine Short
Tech Support Professional Computer Manufacturers
Cape Town, South Africa. Email:ishort (at) pcm dot co dot za

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