atcomsystems.ca/forum Forums General General Telephone & Systems Information Assistance Needed Setting up US Robotics Modem

We have a US Robotics Sportster 33.6 Fax Modem that we need to set up to connect to our ASA. It's my first time using one as we normally use MultiTech modems on our routers which allow us to add the connection string to the AUX port on the router. I've been trying to reverse telnet from my laptop using Hyperterminal but I don't seem to get a connection. I'm using a Cisco rollover cable with a db-9 to rj-45 on my laptop side and a db-25 to rj-45. I'm using the following pinouts for the connections:

DB9 to RJ 45
1 (Blue) DSR(out) 6
2 (Orange) CTS(out) 8
3 (Black) GRD 5
4 (Red) TX(in) 3
5 (Green) RX(out) 2
6 (Yellow) DCD(out) 1
7 (Brown) RTS(in) 7
8 (Gray) DTR(in) 4


RJ-45 DB-25M/F
1 (Blue) DSR(out) 6
2 (Orange) CTS(out) 5
3 (Black) GRD 7
4 (Red) TX(in) 2
5 (Green) RX(out) 3
6 (Yellow) DCD(out) 8
7 (Brown) RTS(in) 4
8 (Gray) DTR(in) 20

I'm not sure what I'm doing wrong or missing, but any help would be greatly appreciated.

I had success using DB9 to DB9 however it has been a while.

You're using the Cisco serial cable! Connect a standard 9/25 modem cable and you won't have any problems.

Yeah I was attempting to use the two db-to-rj connectors and the rolled rj-to-rj cable that Cisco supplies with the ASA for just such an occasion. I'll give it a try using a 9/25 if I can dig one out. Thanks.

If you don't have one - ask. I'm sure someone here has one.

Sam

Did some digging and found one 1 in my old laptop bag. Plan to give it a try this morning.

I tried a standard 9/25 cable with the same results. When I connect using Hyperterminal I get a light on AA, TR, and CS on the modem but no feedback in the program. I'm using 9600/8/N/1 and Hardware for my settings on the COM port.

On the modem side I followed the directions I had: power off modem, dip switch 7 down, power on to reset, power off, reset dip switch 7, power on, connect. I tried copy/paste of the connection string I need in place but when I hit enter I just go back to the Home position on the line.

You could try a null-modem 9/25 cable. Start with a "generic" null modem cable (there are several types but they ALL cross the TX/RX signals). Conversely, if you already use a null modem cable, go for a regular serial one.
Most Cisco serial cables are non-standard/application specific.
Seems like a handshake problem at first glance.
If I may ask, why not go with the modem you already know works?

Try dip switch 4 to on for echo offline with hyperterm.

SPH -- I'd love to go with a modem I know works but the problem is the ones that we normally use, MultiTech's, aren't configurable so I normally at a connection string on the router so it can talk to the modem. Works like a charm. But this time it's a Cisco ASA, which doesn't allow you the same luxury in terms of defining a string. The string has to be on modem itself, so we're using a US Robotics so it we can program it and have it talk to the ASA properly.

I'll give dip switch 4 a shot. I tried a regular serial cable at first. I'll use my null-modem 9-to-9 with a db25 converter to test as well.