AA8IA Amateur Radio

PCC-950 CAT Software requires Hardware Flow Control / Handshaking


If you own a Yaesu FT-950 you probably are familiar with PCC-950, which is the CAT control software that Yaesu provides to allow you to control your radio, manipulate menu settings. etc.

This software communicates over a standard RS-232 serial port. These are the 9-pin and 25-pin rectangular ports most common on the back of PCs. These days, many people do not have bonafide serial ports in their computers and instead have USB ports. For those people in this predicament, you need a USR-to-Serial converter. They are cheap, but some are not fully functional in every aspect and thus are not guaranteed to work in every application that a hardware serial port inside your computer does.

Anyway, on to the point. The PCC-950 software requires hardware flow control / handshaking. If you are using an RS-232 cable between your PC and radio that is not fully wired end-to-end with all of the needed serial port lines/signals, then your setup is not going to be able to meet the hardware flow control requirements of PCC-950. You must have RTS ( pin 7 ) and CTS ( pin 8 ) signaling available from your RS-232 port (or USB-to-Serial adapter) all the way through to the RS-232 jack on the radio, along with various other RS-232 signaling on other pins. You also must have RTS turned ON in the menu settings of the FT-950 (Menu Item #028).

A lot of people roll their own serial cables and for various reasons choose not to have all of the signal lines from the RS-232 port wired through their homemade cable. And, in the case of devices that have built-in Serial-to-USB converters as part of their bigger package, they may not provide all of the signal lines out of their device. I’d venture to say that standalone Serial-to-USB cables all have the appropriate signals available at the RS-232 end of the converter, but whose to say. You never know.

So if you’re trying to use PCC-950 to communicate with your FT-950 and are unable to, but you are able to use other programs for CAT control that don’t use hardware handshaking, then you’ve probably got an issue where either you’ve got an RS-232 cable that isn’t wired correctly for hardware flow control or you have a USB-to-Serial adapter that isn’t providing all of the appropriate signals on the pins that mate with your RS-232 cable.

I don’t write software, and I’m not an electrical engineer, but I have to wonder why in the world PCC-950 wasn’t written with a configurable option to turn off hardware flow control / handshaking. If the option were supported in PCC-950, it’s work with a lot more cable / converter scenarios.

Written by Mike

October 6th, 2010 at 2:57 pm

Posted in FT-950,Posts

Tagged with , , , ,

10 Responses to 'PCC-950 CAT Software requires Hardware Flow Control / Handshaking'

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  1. I have just such a problem, should I tyr a different serial to USB converter? Or another serial 9 pin cable? Thanks 73

    Clifford"Jim" Buck

    25 Nov 10 at 7:41 PM

  2. I can’t get nothing to work PEROID

    Clifford"Jim" Buck

    26 Nov 10 at 12:10 AM

  3. Jim,

    I’ve attempted to assist you as best I could via email. If you are still having problems at this point, I would suggest that you join the FT-950 Yahoo! group and post for assistance there. It’s a large group , and I’m sure somebody will be able to help you.



    28 Nov 10 at 2:21 PM

  4. Clifford"Jim" Buck

    30 Nov 10 at 7:32 AM

  5. RTS on solved my longstanding PCC-950 problem – THANKS! Everything works now…HRD v.5 worked flawlessly but I had RTS off as suggested by HRD users and help files. With RTS on both HRD and PCC-950 work FB. Now I can take advantage of the parametric equalizer in PCC-950….

    Thanks again!


    21 Jan 11 at 2:53 PM

  6. Howard,

    I’m glad to hear you [apparently] found a solution by reading his website. I haven’t done anything at all with the parametric equalizer. I’m going to have to fire up HRD and see what you are referring to. I’m guessing there is a way to manage the equalizer settings / view the equalizer settings when using HRD?


    21 Jan 11 at 3:34 PM

  7. No. He is referring to the capability of PCC-950 to do that, NOT HRD.




    5 Apr 11 at 10:44 AM

  8. I see that, now that you’ve corrected me :) Thanks!


    5 Apr 11 at 11:52 AM

  9. I would like to be familar with this program PCC-950 if someone could tell me where to DOWNLOAD the program!?

    Ivan Williams

    29 Mar 13 at 9:50 AM

  10. AA8IA-Mike

    29 Mar 13 at 9:54 AM

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