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?