I currently have a Java Applet running on my web page that communicates to a display pole via COM1. However since the Java update I can no longer run self-signed Java Applets and I figure it would just be easier to send an AJAX request back to the server and have the server send a response to a TCP port on the computer...the computer would need a TCP > COM virtual adapter. How do I install a virtual adapter to go from a TCP port to COM1?
I've looked into com0com and that is just confusing as hell to me, and I don't see how to connect any ports to COM1. I've tried tcp2com but it doesn't seem to install the service in Windows 7 x64. I've tried com2tcp and the interface seems like it WOULD work (I haven't tested), but I don't want an app running on the desktop...it needs to be a service that runs in the background.
So to summarize how it would work:
EDIT: I'm using Win 7 x64 and tcp2com doesn't work as a service. I tried using srvany but I get an error stating that the application started then stopped. If I use powershell and pass the tcp2com as an argument, it doesn't quit but it also doesn't run. So I nixed the whole 'service' deal and put the command: powershell -windowstyle hidden "tcp2com --test tcp/999 com1" and it works...sort of. The characters that get sent are all effed. I can write "echo WTF > COM1" on another computer which has COM2TCP (different vendor) and it'll come up as a single block on the POS display pole. However if I use COM2TCP on both the server and client machines, everything works fine...but that's only a trial version and it costs several hundred dollars! On another note, is there a way to send the raw text over IP without having to use another Virtual COM > IP adapter on another computer? Sort of like how curl works but different...?
After somewhat of an exhaustive search, I came across a program called 'piracom'. It's a very simple app that lets you specify port settings for the express purpose of connecting a serial port to an listening port over the network. So this is IP > Serial. For Serial > IP I used HW-VSP3-Single as even on the piracom website it said it's compatible! I've tested and it works!
I just put a shortcut to piracom in the startup folder of my user account; the app runs off of a .ini that it updates every time you make a change...so if you run the server and hide it, on the next reboot of the pc it'll start up running and hidden with all prior settings. Easy.
Now it's a matter of installing HW-VSP3 on the server and making a method on the Rails app which will write to the virtual COM port. The only issue I can see right now is that writing echo \14Test This! > COM3 actually prints the \14...if I do that in my Java applet, it sends the "go to beginning" signal.
Addendum 1: The \14 problem was fixed by using the serialport gem for RoR. I created a method in a controller that returned head :no_content and then send data to the COM port. Calls to this method were made via jQuery's $.Ajax, using "HEAD" HTTP method. Apparently though I had to add the GET verb in Rails routes because the HEAD option isn't supported for some gimpy reason.
Addendum 2: Some garbage data was being sent to the display pole at the end of the string...turns out I needed to turn off the "NVT" option in HW-VSP3. Also keep in mind that firewalls need to be modified to allow communication.