QNX 6.1 modem/PPP access?

Can anyone explain to me, or point me to a concise explanation,
how to setup a modem on a QNX 6.1 machine so that I can dial
in to it from a Windows box? I have very little experience in
using modems in this way and would greatly appreciate a little
help on this.

I don’t care if I can run Photon remotely, BTW - a command line window
will serve nicely.


The below thread may be helpful:


This does indeed seem to have most of what I’m after. I think - I won’t know for sure 'til I’m done playing with it.

One immediate question: Randy (the other Randy) describes creating a script, /etc/run_pppd. What runs run_pppd? Does this get started in an rc file? Or what?

I have also read about the use of various forms of getty, which I mostly understand, BUT!. My background is mostly on OSes that use /etc/inittab, but I don’t find it on my QNX 6.1. What is the equivalent way in QNX to start up things like getty?


Back again.

I made the run_pppd script as described in the earlier reference. When I try to run it, I get two errors:

“pppd: too few parameters for option connect”


“run_pppd[4]: chat -vv -f/etc/answer: not found”

On the first, of course some options are in the /etc/ppp/options file. Should I think this is not getting read? And, if so, why not? I have a listing of pppd options, but no indication of which are required for connect.

On the second, I’m not sure what’s “not found”. chat is there, in the path; the usage message for it indicates the options I gave. /etc/answer is there. What am I missing?

Thanks again,

Here is the orginal post from the other Randy:


OK, that helped some more.

Now I can start pppd with the aforementioned options, and it appears to be waiting for RING.

The modem never answers, so now I’m thinking I have either a defective modem, or a modem for which no driver is on the system, or … Also, if I run ‘qtalk -m/dev/ser1’, I get no response to AT commands.

The context, FWIW, is that I inherited a setup running Neutrino, with no manuals or other documentation, except what I can glean out of Photon Help. I don’t find the qnx.com website especially helpful.

Continuing… I have only one serial port instantiated, /dev/ser1. Most discussions here have the modem on ser3. I don’t know if that’s critical (shouldn’t be), but it seems like I might want to setup another one with options appropriate to a modem.

How do you create another serial device? Between Help and web searches, and exploring on my system, I haven’t found it. I need the book “QNX 6.1 System Administration”. Does such a one exist?

Thanks again,

about initializing serial devices, there is a good description with a couple of examples in the “Help” section, under devc-ser8250

as for the modem :

  • does not make a difference, where you connect it to (well, serial port of course)
  • you do not need a driver, starting with qtalk -m /dev/ser1 is very much ok
  • does “ser1” show up when you type “ls /dev” ?
  • did you check the modem with “Hyperterminal” under WIN ?
  • did you try (after starting qtalk) to type “ate1” first, before trying to dial out ?
  • did you check the cable ? sorry if you are familiar with modems and/or troubleshooting, for asking theses questions, but my experience shows that 90% of the problems are with the hardware
  • what does “stty </dev/ser1” answer ?

supposed your hardware checks (under WIN, if you wish to do so) found everything in working order, come back to the forum, and we will have to dig deeper.

about the book :
there have been various posts in the forums, and sometimes there are ads about books from a certain “R.Krten” in the top-right corner of this website, and they received a fair amount of applause from part of the community. the books deal with QNX version 4.xx, and if I dare to say so, without having read them, most things that you learned in QNX v4.xx will be helpful under v6.x too. I myself unfortunately have not been able to lay my hands on them so far … the price is ok, but the shipping costs a fortune (I am living in Germany).
oh, I just made a quick google check, and as I understood, he wrote a book or two about NEUTRINO too. just type in “krten”. … and, by the way : I do not benefit in any way by helping him selling his books. in fact, this is the first time.

good luck

OK, I’ll check that.

Yes on everything up to this point.

No, on all the above. The system is not dual-boot, so I can’t check it on Windows (except by taking the modem out and installing on another computer).

I did not type ate1 at qtalk. I did type at, and there was no response.

And, the modem is internal, so no cabling. But, how can I really be sure that the modem is tied to /dev/ser1? Or what serial port it is connected to? Or how I can configure that?

I’m not at the computer, but I know it dumps a bunch of settings, including handshaking settings, baud rate 57600, parity, etc.

Thanks for the pointer below on the book/author. I’ll see what I can find.


I just read that you use an internal modem.
That changes things, and very much so. There have been different threads about internal modems in the forum. Unfortunately, I am at work now and I have to see a customer, so I might be back not before this evening (German time) to have a look at them and see what we can do.
I the meantime, to openly say, you can look around for a serial modem with cable :frowning:

There is a chance that the internal modem is a soft modem. Unfortunately, QNX doesn’t support such modems. Go get an external serial one which normally is a real/hardware modem.

Got distracted by some other crises for a few days, now I’m back to this.

Yes, I think you’ve probably hit it. There is a strong chance that I have a software modem. I know there are internal hardware modems, and I have in the past installed one in a Linux box and got it to work. I think it was a US Robotics - they have a few models that are true hardware modems.

So I will get one. I’m going internal because this is for a field application where the single external RS232 port is already occupied.

One more question: what about drivers? I know there are Linux drivers for the USR modems. Will they work under QNX, or what do I have to do?


You have to obtain the source and then port it (which is not a simple task) to QNX.

I’ve done some more searching and started to get the impression that the devc-ser8250 driver should do what I need.

Is that not so? (I’ve never ported a driver, and I’d rather not start now.)


If it is a true hardware internal modem, you don’t really need a driver. The standard QNX serial driver devc-ser8250 should just work and create the device /dev/ser? for you.

I’m most of the way there.

I got a hardware modem (3Com/USR 5610).

Then I set up my config like that described by “the other Randy”:

  • Got my device settings via ‘pci -vvvv’
  • ran ‘devc-ser8250 -u2 -t8 dc00,11’
    (option values derived from the first)
  • ran /etc/run_pppd with options at /etc/ppp/options.
  • Now I can dial in, connect and get a telnet session.

BUT, I can’t establish an FTP connection.

I am doing command line FTP from a Win2003 server. I have FTP’d to the target computer previously using my LAN connection.
From the client side, I get "connected to ", but
nothing else, no prompt. After a while it times out and closes.

From the server side, I see (in the syslog file) "connection from ",
“<—220”, “FTP (version) ready”. But there is a serious lag, like a minute or more from the time the client established connection. I suspect that the server computer responds, but just not quite quick enough.

Any thoughts as to what’s happening here?

Thanks again,
Randy C.

A little more info…

I get a substantial lag time on a telnet session before a login prompt comes back, but it does. Once I have the connection the response time is about what you’d expect over a modem.

On the FTP, the client times out in about 60 secs; the server posts its messages to syslog after about 75 secs.

Meanwhile, on the server, as soon as the FTP connection is made, netstat stops working. It will just print out the column headings, then hang.

It feels like some networking related resource on the server is getting tied up. A ps doesn’t show any process spinning out of control. After I kill the connection, it remains tied up - still can’t run netstat.

In syslog, when the connection is made, I see “Cannot determine ethernet address for proxy ARP”. Problem? Also, I assign both systems different IP addresses for the PPP connection than they use over the LAN. Is that a problem?

Many, many more thanks.
Randy C.

Those services (telnetd, ftpd) use dns before it accepts your connection. Your problem sounds like DNS resolution is not working and takes long time to timeout.

A quick solution is to add your client IP on the QNX server’s /etc/hosts file so that telnetd/ftpd can get a dns return immediately.
Long term, you need to figure out why QNX can’t do DNS lookup. Make sure the configured dns servers are accessible from QNX.