Labview 7.0 and Edgeport USB to RS-232

[bde-]

Has anyone had success using 2 Edgeport USB to RS-232 converters with Labview 7.0? I need 19 com ports but only seem to be able to get one of the Edgeport 416 (16 com ports) or the Edgeport 4 (4 com ports) to work at a time with Labview. MAX sees all the ports but I can't seem to access them all from Labview. Is there a maximum com port number? (I'm trying to use com 2-21).

[Broken_Arrow]

Did you install the drivers for the second Edgeport? The computer doesn't know how to map the ports based soley on plugging it in.

Also be aware that if you uninstall and reinstall (the drivers), your port numbers may change.

[bde-]

Yes I installed the driver for both Edgeports and both had COM ports assigned COM 2-18 for the 16 port model and COM 19-22 for the 4 port model. MAX recognized that these ports existed also.

[Matthew_Kelton]

So, in LabVIEW, without changing port numbers on the adapters or diconnecting any of the RS-232 to Serial adapters, you can get one or the other adapter to work?

 Can you use 2 COM ports at the same time in HyperTerminal?

Do you have the adapters on the same USB Root Hub (you'll have to go through your Device Manager to determine this)?  If so, try setting them up on their own Root Hubs (would be a physcially different USB port on the PC).  Perhaps the manufacturer's driver cannot handle the multiple adapters.

How are you determining they don't work?  Is LabVIEW giving you an error, are you just not seeing expected behavior, something else? Are you sure your code is not the source of the problem?

LabVIEW can talk to multiple ports at the same time, and I don't believe the COM22 should be a problem.  If you can talk to COM 22 by itself without issue, then it is not the problem.

[bde-]

In answer to your first question, no, after installing or reinstalling the adapter I can get one adapter only to work, to get the other to work I need to uninstall and reinstall in a different order.

I Didn't try using Hyperterminal

As far as the USB connection, I've tried  two ways, 1) connecting the first 16 port box to the PC's USB and connecting the second 4 port box the 16 port box's expansion USB port. 2) connected each box to it's own PC USB port.

I know the code works I've used it for over a year with no problems, Labview does not talk to the device asevidenced by the device's debug mode display not being activated and the lack of data being returned. If I specify a nonexistant port Labview will time out (as expected) I try a port that is configured and a divice is connected to that port Labview either returns data and the debug display on the device lights up, or Labview does not return data and debug is not lit-up but Labview  does not timeout. If I disconnect the device (from a working port) and repeat, Labview times out and does not return any data (as expected), the odd thing is if I disconnect the device from the non-working port and repeat Labview does not time out or give any error.

I do not try to talk to multiple ports simultaniously. 

[bde-]

Matthew

Thanks you got me thinking on another track and I resolved the problem. First I tried the Hyperterm test  and connected com 2 to com 24 via a null modem and everything worked. Then I dug deeper into the labview issue and found the Modbus driver I was using had a enumerated com port selector (limited to com port 17) instead of a string or numeric input as I expected it had. I fixed that and all works now.