Issue with RS232 <-> USB adaptor (FC15)

Issue with RS232 <-> USB adaptor (FC15)

[f8arr]

Hello Hams !

Apologies for the bandwich, but perhaps someone has allready faced it ...


Here is the case :
In order to have a TX port on WSJT I use /dev/ttyUSB0 from prolific pl2303.
At boot, the serial comes up to TX.
On messages I have only this message :

Jun 13 17:00:08 f8arr2-station kernel: [ 3574.706035] usb 3-1: new full 
speed USB device using uhci_hcd and address 8
Jun 13 17:00:08 f8arr2-station kernel: [ 3574.852805] usb 3-1: New USB 
device found, idVendor=067b, idProduct=2303
Jun 13 17:00:08 f8arr2-station kernel: [ 3574.852814] usb 3-1: New USB 
device strings: Mfr=1, Product=2, SerialNumber=0
Jun 13 17:00:08 f8arr2-station kernel: [ 3574.852819] usb 3-1: Product: 
USB-Serial Controller
Jun 13 17:00:08 f8arr2-station kernel: [ 3574.852823] usb 3-1: 
Manufacturer: Prolific Technology Inc.
Jun 13 17:00:08 f8arr2-station kernel: [ 3574.855943] pl2303 3-1:1.0: 
pl2303 converter detected
Jun 13 17:00:08 f8arr2-station kernel: [ 3574.868109] usb 3-1: pl2303 
converter now attached to ttyUSB0
Jun 13 17:00:08 f8arr2-station mtp-probe: checking bus 3, device 8: 
"/sys/devices/pci0000:00/0000:00:1d.1/usb3/3-1"
Jun 13 17:00:08 f8arr2-station mtp-probe: bus: 3, device: 8 was not an 
MTP device

Of course, If I run WSJT it can't commute the TX with an error message 
"Can't connect to /dev/ttyUSB0"

My user is on the "dialout" and "uucp" group.

I tried exactly the same manipulation with my only real RS232 port and 
it works like a charm.. (but dedicated to an other action).
Of course, same configuration was ok under my ubuntu 10.04. but I 
switched to Fedora 15...

If someone had a idea.. it would be great. My freind google didn't came 
with something looking good...

regards
F8ARR - Guillaume

Re: Issue with RS232 <-> USB adaptor (FC15)

[Dave Platt]

On 06/13/2011 12:24 PM, f8arr wrote:
> Hello Hams !
> 
> Apologies for the bandwich, but perhaps someone has allready faced it ...
> 
> 
> Here is the case :
> In order to have a TX port on WSJT I use /dev/ttyUSB0 from prolific pl2303.
> At boot, the serial comes up to TX.

I'm not certain what you mean here.  Does this mean that the
transmitter is keyed up into TX, as soon as the system boots
and the USB serial port adapter is recognized by the kernel?

If so, this would suggest one of several things:

-  Your PL2303 adapter is asserting either DTR or RTS
   when it is first initialized, without waiting for some
   program to open the USB serial port.

   [Question - which of these lines are you using to drive
    PTT on your transmitter?]

-  Some (unexpected) program is opening /dev/ttyUSB0 as soon
   as the adapter is connected.

> On messages I have only this message :
> 
> Jun 13 17:00:08 f8arr2-station kernel: [ 3574.706035] usb 3-1: new full
> speed USB device using uhci_hcd and address 8
> Jun 13 17:00:08 f8arr2-station kernel: [ 3574.852805] usb 3-1: New USB
> device found, idVendor=067b, idProduct=2303
> Jun 13 17:00:08 f8arr2-station kernel: [ 3574.852814] usb 3-1: New USB
> device strings: Mfr=1, Product=2, SerialNumber=0
> Jun 13 17:00:08 f8arr2-station kernel: [ 3574.852819] usb 3-1: Product:
> USB-Serial Controller
> Jun 13 17:00:08 f8arr2-station kernel: [ 3574.852823] usb 3-1:
> Manufacturer: Prolific Technology Inc.
> Jun 13 17:00:08 f8arr2-station kernel: [ 3574.855943] pl2303 3-1:1.0:
> pl2303 converter detected
> Jun 13 17:00:08 f8arr2-station kernel: [ 3574.868109] usb 3-1: pl2303
> converter now attached to ttyUSB0


> Of course, If I run WSJT it can't commute the TX with an error message
> "Can't connect to /dev/ttyUSB0"

That suggests that either the permissions are wrong, or that some
other program/process has already opened the serial port for
some reason.

> My user is on the "dialout" and "uucp" group.

When the system is in this state, try the following:

	ls -l /dev/ttyUSB0
	lsof | grep ttyUSB0

The output for the first command will show you what
owner/group information was set up for the port during
the hot-plugging.

The output for the second command should help you see
whether there's another program "busying out" the
USB serial port.

> I tried exactly the same manipulation with my only real RS232 port and
> it works like a charm.. (but dedicated to an other action).
> Of course, same configuration was ok under my ubuntu 10.04. but I
> switched to Fedora 15...

That suggests that the adapter itself is OK, and that it's either
an issue of permissions for the port (which would be set via
a configuration file in /etc/udev/), or an issue of some other
program opening the port (maybe something looking for a serial
mouse or a modem?)

Re: Issue with RS232 <-> USB adaptor (FC15)

[f8arr]

Hello My answers inside the email. (Thank you for your reply ;-) )



On 06/13/2011 09:40 PM, Dave Platt wrote:
> On 06/13/2011 12:24 PM, f8arr wrote:
>> Hello Hams !
>>
>> Apologies for the bandwich, but perhaps someone has allready faced it ...
>>
>>
>> Here is the case :
>> In order to have a TX port on WSJT I use /dev/ttyUSB0 from prolific pl2303.
>> At boot, the serial comes up to TX.
> I'm not certain what you mean here.  Does this mean that the
> transmitter is keyed up into TX, as soon as the system boots
> and the USB serial port adapter is recognized by the kernel?

YES

> If so, this would suggest one of several things:
>
> -  Your PL2303 adapter is asserting either DTR or RTS
>     when it is first initialized, without waiting for some
>     program to open the USB serial port.

you are right

>     [Question - which of these lines are you using to drive
>      PTT on your transmitter?]
I'm using DTR

> -  Some (unexpected) program is opening /dev/ttyUSB0 as soon
>     as the adapter is connected.
>
may be.. but witch one ?? grrr


>> On messages I have only this message :
>>
>> Jun 13 17:00:08 f8arr2-station kernel: [ 3574.706035] usb 3-1: new full
>> speed USB device using uhci_hcd and address 8
>> Jun 13 17:00:08 f8arr2-station kernel: [ 3574.852805] usb 3-1: New USB
>> device found, idVendor=067b, idProduct=2303
>> Jun 13 17:00:08 f8arr2-station kernel: [ 3574.852814] usb 3-1: New USB
>> device strings: Mfr=1, Product=2, SerialNumber=0
>> Jun 13 17:00:08 f8arr2-station kernel: [ 3574.852819] usb 3-1: Product:
>> USB-Serial Controller
>> Jun 13 17:00:08 f8arr2-station kernel: [ 3574.852823] usb 3-1:
>> Manufacturer: Prolific Technology Inc.
>> Jun 13 17:00:08 f8arr2-station kernel: [ 3574.855943] pl2303 3-1:1.0:
>> pl2303 converter detected
>> Jun 13 17:00:08 f8arr2-station kernel: [ 3574.868109] usb 3-1: pl2303
>> converter now attached to ttyUSB0
>
>> Of course, If I run WSJT it can't commute the TX with an error message
>> "Can't connect to /dev/ttyUSB0"
> That suggests that either the permissions are wrong, or that some
> other program/process has already opened the serial port for
> some reason.
>

I think that is due to program blocking. Because if I do some 
manipulations with my only real RS232 serial it is working like a charm.
This is due to RS232<->USB (driver?)

>> My user is on the "dialout" and "uucp" group.
> When the system is in this state, try the following:
>
> 	ls -l /dev/ttyUSB0
> 	lsof | grep ttyUSB0
>
> The output for the first command will show you what
> owner/group information was set up for the port during
> the hot-plugging.

crw-rw-rw-. 1 root uucp 188, 0 Jun 13 21:15 /dev/ttyUSB0

(My user is under uucp group)
uucp:x:14:uucp,f8arr
dialout:x:18:f8arr
f8arr:x:500:

> The output for the second command should help you see
> whether there's another program "busying out" the
> USB serial port.
>
nothing...




>> I tried exactly the same manipulation with my only real RS232 port and
>> it works like a charm.. (but dedicated to an other action).
>> Of course, same configuration was ok under my ubuntu 10.04. but I
>> switched to Fedora 15...
> That suggests that the adapter itself is OK, and that it's either
> an issue of permissions for the port (which would be set via
> a configuration file in /etc/udev/), or an issue of some other
> program opening the port (maybe something looking for a serial
> mouse or a modem?)
  I had this in udev rules :

SUBSYSTEM=="usb", SYSFS{idVendor}=="067b", MODE="0666"

with lsusb :

Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 002: ID 0603:00f2 Novatek Microelectronics Corp.
Bus 002 Device 003: ID 046d:c404 Logitech, Inc. TrackMan Wheel
Bus 003 Device 002: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial 
Port
Bus 003 Device 003: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial 
Port

(I have two usb to RS232 adpaters.)



Thaks for help !

Guillaume



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Re: Issue with RS232 <-> USB adaptor (FC15)

[Bruno Tréguier]

Le 13/06/2011 à 21:24, f8arr a écrit :
> mtp-probe: bus: 3, device: 8 was not an MTP device

Hello Guillaume,

Your problem might be related to that bug:

http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=630202

I guess it can occur in other Linux distros, so even if you're not 
running Debian, you might be concerned too.

This bug is still in "open" state, in the meantime, if you don't need 
"libmtp-runtime" (or its equivalent in your distro), the temporary 
solution is to remove it, or at least the "mtp-probe" binary which seems 
to be responsible for this buggy behaviour.

Best Regards,

Bruno - F8FIV
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Re: Issue with RS232 <-> USB adaptor (FC15)

[f8arr]

Hello,

I'm not sure because I found the problem to resolve my issue :

stty --file=/dev/ttyUSB0 clocal

I remove all flow control on the serial.

Has I have two same USB controler, I made a diff from USB0 to USB1 :

# diff usb0 usb1
5c5
<  -parenb -parodd cs8 hupcl -cstopb cread clocal -crtscts
---
>  -parenb -parodd cs8 hupcl -cstopb cread -clocal -crtscts

This is the only difference... maybe there is a configuration somewhere at boot that specify such parameters. Has i'm not really aware of hardware configuration I'll investigate to resolve on the source.
(instead of putting a line on my .profile ;-)

f8arr



On 06/13/2011 09:58 PM, Bruno Tréguier wrote:
> Le 13/06/2011 à 21:24, f8arr a écrit :
>> mtp-probe: bus: 3, device: 8 was not an MTP device
>
> Hello Guillaume,
>
> Your problem might be related to that bug:
>
> http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=630202
>
> I guess it can occur in other Linux distros, so even if you're not 
> running Debian, you might be concerned too.
>
> This bug is still in "open" state, in the meantime, if you don't need 
> "libmtp-runtime" (or its equivalent in your distro), the temporary 
> solution is to remove it, or at least the "mtp-probe" binary which 
> seems to be responsible for this buggy behaviour.
>
> Best Regards,
>
> Bruno - F8FIV
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Re: Issue with RS232 <-> USB adaptor (FC15)

[Bruno Tréguier]

Le 13/06/2011 à 22:28, f8arr a écrit :
> Hello,
>
> I'm not sure because I found the problem to resolve my issue :
>
> stty --file=/dev/ttyUSB0 clocal
>
> I remove all flow control on the serial.
>
> Has I have two same USB controler, I made a diff from USB0 to USB1 :
>
> # diff usb0 usb1
> 5c5
> < -parenb -parodd cs8 hupcl -cstopb cread clocal -crtscts
> ---
>> -parenb -parodd cs8 hupcl -cstopb cread -clocal -crtscts

Ok, sorry for that, I made the wrong assumption that your /dev/ttyUSB0 
device didn't even exist and that it was the reason you could not have 
any access to it.

This is quite strange as (at least as far as I know) PL2303 chips 
usually cope quite well with flow control. I've been using quite a few 
of them here, but never on Fedora Core however (thought I doubt this 
makes any difference here).


> This is the only difference... maybe there is a configuration somewhere
> at boot that specify such parameters. Has i'm not really aware of
> hardware configuration I'll investigate to resolve on the source.
> (instead of putting a line on my .profile ;-)

;-)

Regards,

Bruno - F8FIV
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Re: Issue with RS232 <-> USB adaptor (FC15)

[Dave Platt]

On 06/13/2011 01:53 PM, Bruno Tréguier wrote:
> Le 13/06/2011 à 22:28, f8arr a écrit :
>> Hello,
>>
>> I'm not sure because I found the problem to resolve my issue :
>>
>> stty --file=/dev/ttyUSB0 clocal
>>
>> I remove all flow control on the serial.

I don't think that "clocal" removes flow control (on RTS/CTS) -
that's controlled by a separate option.

What "clocal" does, is "disable modem control signals".
Specifically, for a port marked "-clocal" (not local),
an open() call will block until the device on the port
asserts the CD (carrier detect) line, and if the CD
line is deasserted the port will "hang up".  This is
useful for serial ports connected to dial-up modems,
but not particularly desirable for serial ports being
used to control local devices such as transceiver.

I can't recall whether a -clocal port automagically
asserts DTR even when it isn't open... I don't think so
but I could be wrong.

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Re: Issue with RS232 <-> USB adaptor (FC15)

[f8arr]

hum...

you are right the Issue is not clear.. something is going wrong...
I have to investigate.

73 qro
f8ARR

On 06/13/2011 11:07 PM, Dave Platt wrote:
> On 06/13/2011 01:53 PM, Bruno Tréguier wrote:
>> Le 13/06/2011 à 22:28, f8arr a écrit :
>>> Hello,
>>>
>>> I'm not sure because I found the problem to resolve my issue :
>>>
>>> stty --file=/dev/ttyUSB0 clocal
>>>
>>> I remove all flow control on the serial.
> I don't think that "clocal" removes flow control (on RTS/CTS) -
> that's controlled by a separate option.
>
> What "clocal" does, is "disable modem control signals".
> Specifically, for a port marked "-clocal" (not local),
> an open() call will block until the device on the port
> asserts the CD (carrier detect) line, and if the CD
> line is deasserted the port will "hang up".  This is
> useful for serial ports connected to dial-up modems,
> but not particularly desirable for serial ports being
> used to control local devices such as transceiver.
>
> I can't recall whether a -clocal port automagically
> asserts DTR even when it isn't open... I don't think so
> but I could be wrong.
>
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Re: Issue with RS232 <-> USB adaptor (FC15)

[f8arr]

Hello

Some progress on my acknowledge...

When the PC start, my DTR of my USB-RS232 is up (-6v).
It mean that a program or a daemon is listenning and/or managing my 
serial. I don't want it because i'll use it directly from Wsjt.

If someone has an idear where to search...

73 qro
F8ARR

On 06/13/2011 11:26 PM, f8arr wrote:
> hum...
>
> you are right the Issue is not clear.. something is going wrong...
> I have to investigate.
>
> 73 qro
> f8ARR
>
> On 06/13/2011 11:07 PM, Dave Platt wrote:
>> On 06/13/2011 01:53 PM, Bruno Tréguier wrote:
>>> Le 13/06/2011 à 22:28, f8arr a écrit :
>>>> Hello,
>>>>
>>>> I'm not sure because I found the problem to resolve my issue :
>>>>
>>>> stty --file=/dev/ttyUSB0 clocal
>>>>
>>>> I remove all flow control on the serial.
>> I don't think that "clocal" removes flow control (on RTS/CTS) -
>> that's controlled by a separate option.
>>
>> What "clocal" does, is "disable modem control signals".
>> Specifically, for a port marked "-clocal" (not local),
>> an open() call will block until the device on the port
>> asserts the CD (carrier detect) line, and if the CD
>> line is deasserted the port will "hang up".  This is
>> useful for serial ports connected to dial-up modems,
>> but not particularly desirable for serial ports being
>> used to control local devices such as transceiver.
>>
>> I can't recall whether a -clocal port automagically
>> asserts DTR even when it isn't open... I don't think so
>> but I could be wrong.
>>
>> -- 
>> To unsubscribe from this list: send the line "unsubscribe linux-hams" in
>> the body of a message to majordomo@vger.kernel.org
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Re: Issue with RS232 <-> USB adaptor (FC15)

[Bruno Tréguier]

Le 14/06/2011 à 22:52, f8arr a écrit :
> Hello
>
> Some progress on my acknowledge...
>
> When the PC start, my DTR of my USB-RS232 is up (-6v).
> It mean that a program or a daemon is listenning and/or managing my
> serial. I don't want it because i'll use it directly from Wsjt.
>
> If someone has an idear where to search...

Hi Guillaume,

Have you tried using "fuser" to see which process was using your tty ?

A simple "fuser /dev/ttyUSB0" (preferably as root) should do the trick...

Best regards,

Bruno - F8FIV
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Re: Issue with RS232 <-> USB adaptor (FC15)

[f8arr]

yes..

nothing.. (as root)

But I remember that there was a daemon that was working on serial by 
default on linux.. I'am wrong ?
I'm unable to remember.

f8arr

On 06/14/2011 11:01 PM, Bruno Tréguier wrote:
> Le 14/06/2011 à 22:52, f8arr a écrit :
>> Hello
>>
>> Some progress on my acknowledge...
>>
>> When the PC start, my DTR of my USB-RS232 is up (-6v).
>> It mean that a program or a daemon is listenning and/or managing my
>> serial. I don't want it because i'll use it directly from Wsjt.
>>
>> If someone has an idear where to search...
>
> Hi Guillaume,
>
> Have you tried using "fuser" to see which process was using your tty ?
>
> A simple "fuser /dev/ttyUSB0" (preferably as root) should do the trick...
>
> Best regards,
>
> Bruno - F8FIV
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Re: Issue with RS232 <-> USB adaptor (FC15)

[f8arr]

I found !!!!!!!!!!!!!!!!!!!!!!!!!

The problem came from modem-manager lauched by dbus.
In order to desactivate I had to remove

/usr/share/dbus-1/system-services/org.freedesktop.ModemManager.service

The following trace on /var/log/messages put me on the rails:

Jun 13 14:32:24 f8arr2-station modem-manager[721]: <info>  (ttyUSB0) 
closing serial port...
Jun 13 14:32:24 f8arr2-station modem-manager[721]: <info>  (ttyUSB0) 
serial port closed
Jun 13 14:32:24 f8arr2-station modem-manager[721]: <info>  (ttyUSB0) 
opening serial port...
Jun 13 14:32:24 f8arr2-station modem-manager[721]: <info>  (ttyUSB1) 
closing serial port...
Jun 13 14:32:24 f8arr2-station modem-manager[721]: <info>  (ttyUSB1) 
serial port closed
Jun 13 14:32:24 f8arr2-station modem-manager[721]: <info>  (ttyUSB1) 
opening serial port...
Jun 13 14:32:24 f8arr2-station modem-manager[721]: <info>  (ttyUSB0) 
closing serial port...
Jun 13 14:32:24 f8arr2-station modem-manager[721]: <info>  (ttyUSB0) 
serial port closed


This is working now !!
Thanks everybody for support

Let's go on the rock now (EME) !!!

73 qro
f8arr




On 06/14/2011 11:06 PM, f8arr wrote:
> yes..
>
> nothing.. (as root)
>
> But I remember that there was a daemon that was working on serial by 
> default on linux.. I'am wrong ?
> I'm unable to remember.
>
> f8arr
>
> On 06/14/2011 11:01 PM, Bruno Tréguier wrote:
>> Le 14/06/2011 à 22:52, f8arr a écrit :
>>> Hello
>>>
>>> Some progress on my acknowledge...
>>>
>>> When the PC start, my DTR of my USB-RS232 is up (-6v).
>>> It mean that a program or a daemon is listenning and/or managing my
>>> serial. I don't want it because i'll use it directly from Wsjt.
>>>
>>> If someone has an idear where to search...
>>
>> Hi Guillaume,
>>
>> Have you tried using "fuser" to see which process was using your tty ?
>>
>> A simple "fuser /dev/ttyUSB0" (preferably as root) should do the 
>> trick...
>>
>> Best regards,
>>
>> Bruno - F8FIV
>> -- 
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Re: Issue with RS232 <-> USB adaptor (FC15)

[Bruno Tréguier]

Le 14/06/2011 à 23:20, f8arr a écrit :
> I found !!!!!!!!!!!!!!!!!!!!!!!!!
>
> The problem came from modem-manager lauched by dbus.
> In order to desactivate I had to remove
>
> /usr/share/dbus-1/system-services/org.freedesktop.ModemManager.service
>
> The following trace on /var/log/messages put me on the rails:
>
> Jun 13 14:32:24 f8arr2-station modem-manager[721]: <info> (ttyUSB0)
> closing serial port...
> Jun 13 14:32:24 f8arr2-station modem-manager[721]: <info> (ttyUSB0)
> serial port closed
> Jun 13 14:32:24 f8arr2-station modem-manager[721]: <info> (ttyUSB0)
> opening serial port...
> Jun 13 14:32:24 f8arr2-station modem-manager[721]: <info> (ttyUSB1)
> closing serial port...
> Jun 13 14:32:24 f8arr2-station modem-manager[721]: <info> (ttyUSB1)
> serial port closed
> Jun 13 14:32:24 f8arr2-station modem-manager[721]: <info> (ttyUSB1)
> opening serial port...
> Jun 13 14:32:24 f8arr2-station modem-manager[721]: <info> (ttyUSB0)
> closing serial port...
> Jun 13 14:32:24 f8arr2-station modem-manager[721]: <info> (ttyUSB0)
> serial port closed

Well done ! But it's rather strange that "fuser" didn't give away the 
name of the culprit... As the modem-manager application seems to keep 
opening and closing the ttys, you must have been unlucky and "fuser" 
checked just when the port was closed...


> This is working now !!
> Thanks everybody for support

Well, thanks to you, as there is no doubt this kind of information is 
useful for everybody. We can all be victims of those little processes 
launched without notice (usually at session startup time). Linux is 
becoming too complicated sometimes, haha ! :-)


> Let's go on the rock now (EME) !!!

Good luck ! Maybe we'll have the opportunity to make a QSO via 
moonbounce one day: I'm a member of F6KHM here in Brest, and we have a 
nice 10.30m dish, that we use for EME too. ;-)

Best regards,

Bruno - F8FIV
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