Cygwin Windows --> Accessing serial port.

R M rm.engineer84 at gmail.com
Sat Jun 25 17:43:10 UTC 2011


Hi Dieter,

I was going through the archieves and I came across a mail that you
sent on the topic of noisy cabe. I have copy pasted the msg below:

My experience: I work under Windows with Cygwin so the OS internals
how the serial port is handled are (totally) different than Linux.
With the non-blocking variant of "osmocon" it was nearly impossible
to download the code to the phone in a reliable way. So I had to apply
an ugly hack to my version which basically switches the serial connection
to "blocking mode" during the download phase. This way it works rather
reliable here (regardless of using a "real" RS232 port or an USB to serial
converter).

So you might experience the same problem instead of a bad cable. You
can try the attached patch to "osmocom.c". The patch is not for the
latest GIT version, however it should be quite easy to apply it to
the current on. Again, its an ugly hack, but it works for me.

Best regards,
  Dieter


I too work under cygwin environment but under windows 7.

I am not able to download the code on to my phone though my cable
seems to be fine. (I am using the Prolific USB to serial converter and
have performed a loop back test to verfiy the cable)

Can you please provide me the patch for the present version of
osmocon.c as you mentioned in the mail as I am unable to apply the
patch manually.

Thanks and Regards,
RM


On Sat, Jun 18, 2011 at 7:28 PM, R M <rm.engineer84 at gmail.com> wrote:
> Hi,
>
> If I have a prolific usb to serial converter can I be sure that the
> voltage levels that I get is 3.3V and not 5V.
>
> My serial cable seems to be fine. I have done a loopback test and its
> echoing whatever I have typed using hyperterminal.
>
> My mobile phone's audio jack is also fine. I am able to use the hands
> free feature and listen to the voice.
>
> I hence feel that the 2.5mm male connector of the serial cable is not
> properly connecting to the audio jack of the phone though it sits
> properly.
>
> Is there a way I can rectify this without buying a new serial cable?
>
> Regards,
> RM
>
> On Mon, Jun 13, 2011 at 12:45 AM, Arne <zachso at arcor.de> wrote:
>>
>> the 3v3 version of max232 is max3232, but this isnt what he needs.
>>
>> RM, you need a usb->RS232 only if you have no RS232 at one of you
>> computers/notebooks available. if you have a normal RS232-port you have
>> already everything you need and can use you cable
>>
>> bye
>> arne
>>
>>
>> On Sun, 12 Jun 2011 20:53:49 +0200
>> Sébastien Lorquet <squalyl at gmail.com> wrote:
>>
>> > If you want to use a basic serial port, use a 3.3V version of the
>> > good ol' MAX232 (maybe MAX202? can't remember)
>> >
>> > Sebastien
>> >
>> > On Sun, Jun 12, 2011 at 8:20 PM, Alexander Huemer
>> > <alexander.huemer at xx.vu>wrote:
>> >
>> > > On Sun, Jun 12, 2011 at 11:11:37PM +0530, R M wrote:
>> > > > Why do I need a USB/RS232 cable ?
>> > > >
>> > > > If its a laptop, I can understand that they don't come with a
>> > > > serial port
>> > > so
>> > > > you need the converter.
>> > > >
>> > > > Many PCs come with a serial port.
>> > > >
>> > > > Can I not connect the serial version of the T191 unlock cable to
>> > > > PC
>> > > serial
>> > > > port?
>> > > You could, but the RS232 ports that are often present on ATX-style
>> > > mainboards provide 12V, which is too much for the phone.
>> > > >
>> > > > As far as I understand, the T191 unlock cable is used to convert
>> > > > RS232 signal level to 3.3V required by C128.
>> > > no. A serial T191 cable does nothing by itself.
>> > > >
>> > > > Since I was able to get hold of a serial version of T191 unlock
>> > > > cable as
>> > > I
>> > > > told you in the begining of the mail, I also purchased a USB to
>> > > > Serial converter. Its a BAFO BF-810.
>> > > > Its based on Prolific chipset.
>> > > Unfortunately the prolific chips seem to not work as well for this
>> > > purpose as the FTDI chips.
>> > > >
>> > > > So I connected first the USB/RS232 converter  ju(BAFO BF-810) and
>> > > > then
>> > > the
>> > > > serial version of the T191 unlock cable.
>> > > >
>> > > > Is this the right way ?
>> > > >    OR
>> > > > Can I just connect the USB/R232 converter (based on Prolific
>> > > > chipset) and the use a cable which contains DB9 female on one
>> > > > side and 2.5mm jack on
>> > > the
>> > > > other?
>> > > I don't get the difference between those two ways.
>> > > >
>> > > > I am asking the second question because you have mentioned in the
>> > > > wiki
>> > > under
>> > > > Hints and Warnings like this:
>> > > >
>> > > > If you don't use a 3.3V (low voltage TTL, LVCMOS) serial port you
>> > > > can fry your phone! (internally, it connects to the IO-pins of
>> > > > the baseband processor which run at 2.8V). *Don't connect
>> > > > directly to your PCs serial port (running at +/- 12V!).*
>> > > This warning wants to tell you that you should use a USB<-->RS232
>> > > converter and not use an onboard port of a PC.
>> > >
>> > > Kind regards
>> > > -Alex
>> > >
>> > >
>>
>>
>




More information about the baseband-devel mailing list