Re: [wsjt-devel] WSJT-X PTT issues when using 2nd serial port

[Bill S. <g4...@cl...>]

On 13/04/2015 07:35, Gennaro Antonio Zaza wrote:
> Dear Joe.
Hi Gennaro,

firstly I am answering becuase I deal with most of the rig control areas 
of WSJT-X.
>
> I tried installing the latest version of WSJT-X v1.4.0-rc2 r4403 on a
> Ubuntu 14.04 64bit machine and found the following problem, which seems to be
> a bug.
That is not the latest version and there have been relevant changes 
released since then. The current release is WSJT-X v1.4.0 and you can 
find suitable download links on the project web page here:

http://www.physics.princeton.edu/pulsar/K1JT/wsjtx.html

or from the project SourceForge files area here:

https://sourceforge.net/projects/wsjt/files/wsjtx-1.4.0/

>
> But first let me describe the hardware.
>
> Rig is an Icom IC-756PROII Connected via CI-V to USB converter cable to
> computer.
>
> Radio's Microphone and audio are connected via an MFJ-1275 (Sound Card
> Radio Interface) This interface is connected via a second Serial to USB
> converter. The Input/Output Audio signals are connected to sound
> card of Computer.
OK, so this second serial interface is only for PTT.
>
> I can also tell you that flrig/fldigi do not exhibit any issues with
> this same hardware configuration, working correctly in all the digital
> modes it supports.
>
> The WSJT-X Settings are:
>
> Rig: Icom IC-756PROII Poll Interval (1 s)
> CAT Control
> /dev/ttyUSB0
>
> Serial Port Parameters: Baud Rate=as per Icom, Data Bits=8, Stop Bits=2
>
> Handshake = NO and Forced DTR / RTS = NO
>
> PTT Method = RTS
>
> Port: /dev/ttyUSB1
>
> THE ISSUE: The rig goes to TX as soon as the software is started.
>
> The WHY: The RTS / DTR lines behave in a weird way with this software
This is due to a defect that causes the serial port to open briefly when 
all the ports are scanned. On Linux and Mac opening a port will raise 
DTR & RTS unless special action is taken to stop that happening. This 
defect is not in the latest release.
> If PTT Method=RTS, when [Test PTT] is toggled RTS does toggle ON/OFF.
> However DTR remains asserted ON all the time.
>
> If PTT Method=DTR, when [Test PTT] is toggled then DTR toggles ON/OFF.
> However RTS remains asserted ON all the time.
Both of these behaviours are consistent with opening the port normally 
except that the control line selected for PTT is held low until PTT is 
asserted. This would not normally be a problem.
>
> Why is this happening!
> The MFJ-1275 schematics shows that the RTS/DTR are ored to the same
> transistor so that the user can select either one to control the rig's
> PTT line.
This is the first time I have come across such a configuration in a 
radio interface! We have not allowed for such a set up and you are the 
first to report this issue.
>
> Also I noticed that if I set the Test PTT to ON on the Settings page AND
> hit the Test CAT button, the Serial port RTS/DTR are reset both to off.
> However further clicks on the Test PTT button yield no changes to either
> lines.
That is because the port gets closed during reconfiguration.
> They return to the previous condition when the Test CAT Button is
> pressed again. The OTHER unselected control line is ON always.
>
> I hope you can use this information to improve on the functionality of
> the software, meanwhile I will hack the interface by not feeding one of
> the control signals to the MFJ box.
That is a suitable quick solution if you are happy modifying your serial 
cable or interface.

I have considered changing the "Force control line" check boxes to some 
sort of tri-state widget that allows set on, set off or, leave alone. I 
am reluctant to implement the apparently obvious feature of just having 
force on or force off as this will interfere with normal operating 
system RS-232 modem control usage which may be used in remote connections.

I will look at a change to resolve this issue and get back to you soon.
>
> Much appreciation for your work on improving digital modes on Ham Radio
> and many thanks for your time reading this, accept
>
> Warmest regards and
>
> 73 de W4BFL.
73
Bill
G4WJS.