Monday, June 09, 2014

Quick & dirty RS422 VTR control from your laptop

If you need to control a deck (or test routes through an RS422 matrix) then a very quick and easy way of doing it is via your laptop. Modern machines don't have RS232 ports and so you can't just hook up an RS232-422 balancer, but USB serial devices are cheap - the Addenda RS-USB4 is the one I keep in my rucksack.



It's worth noting some of the settings you need for the serial port in Windows.


You then need a bit of software that will talk the P2 protocol. WSony II has been around forever but still works under Windows7. You have to run it as admin for it to access the serial port.

Once it runs you have to tell it what port number gave it - It shows up as Com1 on my machine by default, but bear in mind that Windows will often assign it to Com5 or greater. The WSonyII will only talk up to Com4 so you might need to change that (see the first image above in the advanced tab).

Now you've got everything you need to drive a VT or test that an RS422 circuit is working.

Oh, if you don't have the CD that came with the Addenda adaptor cable you'll need to download the software here.

Remember; P2 over RS422 runs at 38,400 baud.

3 comments:

phil hofstetter said...

On my 64Bit computer, WSony II wouldn't run - but I found another tool that works and emulates Sony 9pin (old and free, too):
http://www.easycode.cat/English/ActiveX.htm

Thanks for writing that interesting blog!

Another Phil from Switzerland

Chris said...

Phil,

I have a particularly baffling issue. I have a Sony EVO-9720 with an RS-232C port to which I have a Kramer VP-43XL Serial RS-232 to RS-422 bidirectional converter attached. Then I have a Vuetech Vuefinder jog shuttle controller attached to the Kramer as well, but I can't get them to communicate. About the only thing I can achieve is Tape Stop when I press the stop button in rapid succession. All other functions do not work. Do you have any suggestions?

Chris

Phil Crawley said...

This is really going back a bit! IIRC the RS232C port on a EVO-9720 is not P2/RS422 (38kits VTR-control) rather it is a version of LANC (widely used in medical and other non-broadcast industries); again, around twenty years ago there was a box (Michael Sellman?) that could convert between the protocols and it was a lot more than just balancing/unbalancing.
I'll ask around at the office with some of the grey-hairs and see if they can remember any more than me!