sundance-communications.com/forum Forums TDM Business Telephone Systems Comdial Telephones & Systems DSU Serial Ports

I got called out to a place that has a DSUII (gray) L1632. I believe this is just a DSUII also, but normally they are black. I'm a little rusty on this one since I was probably in high school when this thing was made.

I checked program 15 and the ports are definitely set at 9600-8-1. I am unable to get my laptop to connect to any of the ports... Com 1-4. I tried restarting he phone system just in case a port was locked up. I think that I've connected to this in the past, but I'm not 100% positive. Would it be likely for all four ports to have something wrong with them? I tried my laptop serial port and also and usb to serial and cannot get any response with hyperterminal or putty.

Any suggestions?

On your computer you need to be sure that flow control is set to off. You also need to be sure that your adapter you are using is wired correctly, The most common issue is that when the serial to rj11 interface was made it was either made for a standard line cord or a straight through line cord and you are using the other.

db9 pin 2 to rj pin 4 (RD)
db9 pin 3 to rj pin 3 (TD)
db9 pin 5 to rj pin 2 (SG)
optional
db9 pin 8 to rj pin 5 (CTS)

this is based on a 6 pin rj11 as per the manual

On an informational note
Comdial made the DSU and the DSUII. The DSU was a black cabinet and the DSUII was a grey cabinet. Depending on who you ask you may or may not be able to interchange modules.

I believe the connector I'm using actually came from comdial back in the day. I think we ordered a bunch of them. Unless the connector went bad in my bag, it was probably last used on an FX-II a few months ago.

As for flow control, I'll have to check my settings in hyper terminal. I had a saved profile that I used.

I feel like it has to be the cabinet, but I can't imagine all 4 ports having an issue. Then again this 21 year old hardware LOL

If you recently used it, then it may just be a line cord issue. Not sure on Putty, but hyperterm I know likes to default flow control to on. You might also go in the hard way and change the serial settings. I know on the FXII you can change the send and receive settings separately (don't do that you won't be able to connect).

Stupid question on the line cords: Would a line cord that works on an FX w/ VMMI not work on a DSUII? I assume it would. I don't think I've ever used a straight through line cord for programming - always just a standard line cord. My next step is to test that adapter. Maybe I'll have to order one of those DIY adapters from Amazon.

Should be a regular line cord. If you have two of the adapters and two pcs you could try to talk between.

I just shorted pins 3-4 on a RJ-11 keystone jack. Plugged in and tested with hyperterminal and I could see what I was typing. All the local echo settings are off. So, I'd say the issue was that DSUII. The stuff in my old timey laptop bag doesn't get used often, but I do believe it's all good. If I ever go back there I'll try again, but I'm thinking something is toast on the DSUII. I ended up using the block programming feature to copy the stations from the attendant extension.