USB Modem

[Neil Waldhauer]

I think I need a modem for a modern computer that lacks a standard serial port. So probably a USB modem. I remember the problems with WinModems, and I think those problems are still there. But I think I have a reasonable modern modem that would work with our USB com driver.

Does anyone have any idea if this would work?

https://www.cdw.com/product/us-robotics-56k-usb-fax-modem/1429761

[Rich Walsh]

Does anyone have any idea if this would work?

I think the key is this line from the product datasheet:

This controller-based modem integrates powerful communications processing functions into the modem itself, for assured performance without sapping your computer’s processing power.

IOW, it sounds like it's a real modem that does the work itself instead of foisting it off on Windows.

[Dave Yeo]

Yes, I used those while stuck on dial up. Only the Arca Noae USB drivers worked with it and they're very sensitive to lightning, I went through two. Luckily they were cheap at the local drug store due to being discontinued.
Actually might have been a different modem that only worked with the Arca Noae USB drivers. Anyways other then the lightning problems, they were fine on my crappy landline. IIRC, you do have to install the supporting USB drivers.

[Dave Yeo]

Another thing was that using the Injoy dialer's NAT, I had to kill socktidy or not load it. IIRC, all it needed was the basic ATZ to initialize it.

[Neil Waldhauer]

I got a US Robotics 5637 USB modem and plugged it in. I installed USBCOM.SYS with no command line switches

Mode COM1
SYS0020: The system cannot find the device specified.


The output of usbtree.exe:

Code: [Select]

USB driver version = 12.10
----- USB device tree ---------------------------------------------------------
DS 07a0=777c

Controller 0: USBXHCD$
Root Hub 0 (16 ports) 8086:31A8
  Port 4: Device 0BAF:0303  HS U.S. Robotics
  Port 5:  Hub 1 (4 ports) 0557:7000 (FS hub) ATEN International Co., Ltd Hub
    Port 1: Device 04D9:2013 (HID)-(Keyboard)(HID)-(Mouse) LS Holtek Semiconductor, Inc.
    Port 4: Device 093A:2510 (HID)-(Mouse) LS Pixart Imaging, Inc.
  Port 8:  Hub 2 (4 ports) 05E3:0610 (HS hub with multiple TT) Genesys Logic, Inc.


[Dave Yeo]

Found mine. First doing mode com1 gave me an error about no com port installed. Installed USBCOM.SYS and rebooted.

Code: [Select]

USB driver version = 12.11
----- USB device tree ---------------------------------------------------------
DS 07f0=7798

Controller 0: USBXHCD$
Root Hub 0 (4 ports) 1B21:2142

Controller 1: USBEHCD$
Root Hub 1 (2 ports) 8086:1C2D
  Port 1:  Hub 3 (6 ports) 8087:0024 (HS hub with single TT) Intel Corp. Integr
    Port 3: Device 046D:C534 (HID)-(Keyboard)(HID)-(Mouse) FS Logitech, Inc. Un
    Port 4: Device 0BAF:0303  HS U.S. Robotics USR5637 56K Faxmodem

Controller 2: USBEHC2$
Root Hub 2 (2 ports) 8086:1C26
  Port 1:  Hub 4 (8 ports) 8087:0024 (HS hub with single TT) Intel Corp. Integr

Z:\Mozprofiles\Downloads>mode com1
baud     = 9600                   parity   = NONE
databits = 8                      stopbits = 1
TO       = OFF                    XON      = OFF
IDSR     = OFF                    ODSR     = OFF
OCTS     = OFF                    DTR      = ON
RTS      = ON                     BUFFER   = N/A

Do you have com.sys installed? The modem takes the first free port IIRC, try com2, etc.

Edit: I see usbtree shows yours as the same device ID but a different description, hopefully they haven't changed its firmware.

[Neil Waldhauer]

I saw that you were working with a USB 2 connection. I tried that too, but no change. I may as well open an incident with Arca Noae.

This modem ought to work. Here is the support site. They support Windows 2000...

https://support.usr.com/support/product-template.asp?prod=5637

[Dave Yeo]

I tried the USB3 controller, same results. I am on the 12.11 drivers, not that that should matter. All I can assume is that yours has a different firmware version.

[Dave Yeo]

Be good to test under a different operating system too as the modem could be defective.

[Neil Waldhauer]

Although I don't like to touch other operating systems, I tried plugging the modem into Ubuntu desktop.

I have no idea how to use a modem under Linux, but lsusb does show the device, and ls /dev shows a new device /dev/ttyACM0 that appears when I plug in, and disappears when I unplug.

It turns out OS/2 is assigning the serial port to COM10.

Device=usbcom.sys /N:COM1

is required to assign the modem to COM1. Now I have to remember how a modem works...

[Neil Waldhauer]

I'm using IBM Dialer (SLIPPM) to try to make a connection with the modem. The modem seems to respond with OK to an initialization command, but then the dialer never seems to actually dial.

I remember, a long time ago, modems used to have a speaker and make quite distinctive sounds when they connected. I wish that was happening here.

[Dave Yeo]

I have a vague memory of having problems with DOIP, though it may have been just frustration with no dial on demand.
What initialization string are you using? While it seems I had a complicated one at one time, I settled on AT then ATZ and ATDT######### for the dialing in part.
Could always test with Injoy, https://hobbes.nmsu.edu/download/pub/os2/util/network/dialer/InJoyDialer_3-0.zip which is what I used.
After a lightning storm, I could never dial in again, happened with 2 modems and afterwards acquired a computer with a serial port and switched back to a USR Sportster. I believe the one I found here is broken but no longer have a land line to test. Strangely I still have the dial up account, get a bill every month for negative $3, maybe so Telus can legally spam me.

[Neil Waldhauer]

There is no speaker in this modem, so I attached a phone handset to the line, and I listened to it as I made my connection.

The first attempt got a “We're sorry, your call can not be completed as dialed” message. My phone does not need a “9” in order to access an outside line.

I accessed OS/2 Dialer settings and changed the phone number to remove the “9,”. Listening in using my handset I can hear it negotiate for a while, then the connection is good. Now I get a PAP authentication error. I tried the default modem strings, and also the ones you posted above, but there is no change.

It's been a long time since I listened to the modem song as it negotiates the connection.

I think I have the userid and  password, right, so what else can cause PAP authentication error?

[Dave Yeo]

Needing CHAP? https://www.geeksforgeeks.org/difference-between-pap-and-chap/
What kind of system are you logging into? IIRC, Windows liked CHAP.
There's also just the timing of doing PAP, everything has to flow at the right speed.
BTW, have you noticed the program modemtst.exe?

[Neil Waldhauer]

I didn't know about modemtst.exe, and it is a great tool for modems, and probably for serial ports testing in general. This proves the modem works and it is just a password issue.