USB to null serial

[cybercop23]

Here's the issue.
I have a Zebra label printer that can connect null-serial, USB or parallel. My application only works with COM ports.

I know I can buy a cable that will convert USB to serial and this will create a 'virtual' COM port. If I do this I also need to get a null modem gender-bender, since I can't seem to find any USB to null serial adapters.

What I want to do, is connect the printer to the PC via USB and run some kind of low level software and/or drivers that will create virtual COM ports and 'fake' my application into thinking it connected via serial when in actuality it is connected USB.

Any ideas? If there are better forums to post this to, please let me know. Any help would be very appreciated.

Thanks
AB

 

[daronwilson]

There are many USB devices that replicate a serial port out there, if your application is windows based it should be no problem to pick up one of those, set it up as Com1, and use a null modem (if you need to). I'm not sure why you would need a null modem, that is generally used when two like devices are hooked together (PC to PC). Peripherals (generally) are designed to connect with a straight serial connection to the computer.

If your application is DOS based, you may have a problem. I've experienced some problem with some USB serial port replicators that won't handle the older DOS calls and support the serial port.

Good Luck!

It is only my opinion, based on my experience and education...I am always willing to learn, educate me!
Daron J. Wilson, RCDD
daron.wilson@lhmorris.com

 

[franklin97355]

If the printer connects to a null serial port why do you need to go usb? You should be able to connect to the comm port directly. (I would think)

 

[daronwilson]

Good point, I was assuming it was a newer laptop without a serial port.

It is only my opinion, based on my experience and education...I am always willing to learn, educate me!
Daron J. Wilson, RCDD
daron.wilson@lhmorris.com

 

[cybercop23]

My issues are with all the different connections that I need to make in order to get it to work and further more support it when it gets in the field. I can get an USB to serial cable (tested it and it worked) and then I need to also connect a null modem converter (since I haven't yet been able to find an USB to null serial cable). All these cables and connectors make things harder to replace and troubleshoot. The printer has both null-serial and USB. It will make things alot easier if I could conect the printer USB. My Windows98/2K application communicates serial via COM ports. So what I need to do is somehow get Windows to allow a "pass-through" making my application think it's communicating via a COM port.

 

[franklin97355]

Sounds like you need to rewrite your application to work with todays technology. You could write a driver that takes care of this but that might take as much time as changing the application.