FTDI FT232BM Hyperterminal Problems

Hi.  I'm working on a project where I am connecting a Garmin OEM GPS
Receiver (asynchronous, RX-TX-GND) through the USB port in Windows XP.
Initially I connected the GPS through COM1 and successfully received
the data in HyperTerminal.  The GPS sends data at the factory default
of 4800, 8N1.  The GPS sentence length is 55 bytes plus a LF and CR at
the end, one sentence per second. (only the $GPGGA sentence)

Now I am trying to receive the same data via the USB port using a DLP
Design DLP-USB232M USB Adapter.  I downloaded the Virtual Com Port
(VCP) drivers and installed them.  The installed drivers show up in
the device manager as "USB Serial Port (COM4)".  It is set to 4800,
8N1 under Properties.

When I try to connect to COM4 in HyperTerminal, I only receive
garbage.  The data displayed in the HyperTerminal window does not
resemble the data seen from the connection on COM1 and is not the same
length.

I ran "Test Application V1.0" from DLP and when connected to COM1 it
receives 113 bytes of data at a time.  When connected to COM4, 113
bytes are also received.

The DLP board is seated in a solderless breadboard.

Does anybody know what might be going on?

C. Bremer

"C Bremer" <cdbremer@gmail.com> wrote in message 
news:9ec041b7.0502260348.3ad066e@posting.google.com...
> Hi.  I'm working on a project where I am connecting a Garmin OEM GPS
> Receiver (asynchronous, RX-TX-GND) through the USB port in Windows XP.
> Initially I connected the GPS through COM1 and successfully received
> the data in HyperTerminal.  The GPS sends data at the factory default
> of 4800, 8N1.  The GPS sentence length is 55 bytes plus a LF and CR at
> the end, one sentence per second. (only the $GPGGA sentence)
>
> Now I am trying to receive the same data via the USB port using a DLP
> Design DLP-USB232M USB Adapter.  I downloaded the Virtual Com Port
> (VCP) drivers and installed them.  The installed drivers show up in
> the device manager as "USB Serial Port (COM4)".  It is set to 4800,
> 8N1 under Properties.
>
> When I try to connect to COM4 in HyperTerminal, I only receive
> garbage.  The data displayed in the HyperTerminal window does not
> resemble the data seen from the connection on COM1 and is not the same
> length.
>
> I ran "Test Application V1.0" from DLP and when connected to COM1 it
> receives 113 bytes of data at a time.  When connected to COM4, 113
> bytes are also received.
>
> The DLP board is seated in a solderless breadboard.
>
> Does anybody know what might be going on?

Try RealTerm (it's free). It's much better than Hyperterminal for sorting 
out comms problems.

Leon
-- 
Leon Heller, G1HSM
http://www.geocities.com/leon_heller 

C Bremer wrote:
> Hi.  I'm working on a project where I am connecting a Garmin OEM GPS
> Receiver (asynchronous, RX-TX-GND) through the USB port in Windows
XP.
> ...
> When I try to connect to COM4 in HyperTerminal, I only receive
> garbage.  The data displayed in the HyperTerminal window does not
> resemble the data seen from the connection on COM1 ....
>
> Does anybody know what might be going on?

I also found HyperTerminal hopelessly buggy and unusable; in addition
to Leon's suggestion I can recommend Takashi Teranishi's Tera Term
(Pro): http://hp.vector.co.jp/authors/VA002416/teraterm.html which
worked perfectly for me.

> 
> C. Bremer

"C Bremer" <cdbremer@gmail.com> wrote in message 
news:9ec041b7.0502260348.3ad066e@posting.google.com...
> Hi.  I'm working on a project where I am connecting a Garmin OEM GPS
> Receiver (asynchronous, RX-TX-GND) through the USB port in Windows XP.
> Initially I connected the GPS through COM1 and successfully received
> the data in HyperTerminal.  The GPS sends data at the factory default
> of 4800, 8N1.  The GPS sentence length is 55 bytes plus a LF and CR at
> the end, one sentence per second. (only the $GPGGA sentence)
>
> Now I am trying to receive the same data via the USB port using a DLP
> Design DLP-USB232M USB Adapter.  I downloaded the Virtual Com Port
> (VCP) drivers and installed them.  The installed drivers show up in
> the device manager as "USB Serial Port (COM4)".  It is set to 4800,
> 8N1 under Properties.
>
> When I try to connect to COM4 in HyperTerminal, I only receive
> garbage.  The data displayed in the HyperTerminal window does not
> resemble the data seen from the connection on COM1 and is not the same
> length.
>
> I ran "Test Application V1.0" from DLP and when connected to COM1 it
> receives 113 bytes of data at a time.  When connected to COM4, 113
> bytes are also received.
>
> The DLP board is seated in a solderless breadboard.
>
> Does anybody know what might be going on?
>
> C. Bremer

When you start your HyperTerminal, click Call -> Disconnect, then click 
File -> Properties then confirm you're using the com port you think you are. 
Next click the Configure button and confirm the baud setting are correct for 
your interface.  Make sure you select None for Flow Control.  Save 
everything then click Call -> Call.  It should be OK.

I've run through this a few times in trying to get a HyperTerminal session 
working correctly.  I have successfully gotten an FTDI / USB adapter to work 
with the three wire serial interface to a GPS at 4800N81.

HTH

Dave

i use the fdti chipset for com with and without hyperterminal , conclusion 
no problem , i also use an usb dual serial adapter with 2 ftdi , and i have 
the same conclusion.
Perhaps , effectively the bug with hyperterminal when changing the 
parameters and not connect and disconnect , but this bug is with all sort of 
com .
i try to avoid the usb serial behind usb HUB , because i get some energy 
economy disconnect , that all.
in particular i use picstart plus on com3 and prototype board on com4.


"C Bremer" <cdbremer@gmail.com> a &#4294967295;crit dans le message de news: 
9ec041b7.0502260348.3ad066e@posting.google.com...
> Hi.  I'm working on a project where I am connecting a Garmin OEM GPS
> Receiver (asynchronous, RX-TX-GND) through the USB port in Windows XP.
> Initially I connected the GPS through COM1 and successfully received
> the data in HyperTerminal.  The GPS sends data at the factory default
> of 4800, 8N1.  The GPS sentence length is 55 bytes plus a LF and CR at
> the end, one sentence per second. (only the $GPGGA sentence)
>
> Now I am trying to receive the same data via the USB port using a DLP
> Design DLP-USB232M USB Adapter.  I downloaded the Virtual Com Port
> (VCP) drivers and installed them.  The installed drivers show up in
> the device manager as "USB Serial Port (COM4)".  It is set to 4800,
> 8N1 under Properties.
>
> When I try to connect to COM4 in HyperTerminal, I only receive
> garbage.  The data displayed in the HyperTerminal window does not
> resemble the data seen from the connection on COM1 and is not the same
> length.
>
> I ran "Test Application V1.0" from DLP and when connected to COM1 it
> receives 113 bytes of data at a time.  When connected to COM4, 113
> bytes are also received.
>
> The DLP board is seated in a solderless breadboard.
>
> Does anybody know what might be going on?
>
> C. Bremer 

"Leon Heller" <leon_heller@hotmail.com> wrote in message news:<42206ea7$0$2761$cc9e4d1f@news-text.dial.pipex.com>...
> "C Bremer" <cdbremer@gmail.com> wrote in message 
> news:9ec041b7.0502260348.3ad066e@posting.google.com...
> > Hi.  I'm working on a project where I am connecting a Garmin OEM GPS
> > Receiver (asynchronous, RX-TX-GND) through ...............

> Try RealTerm (it's free). It's much better than Hyperterminal for sorting 
> out comms problems.
> 
> Leon

I downloaded Realterm and I get pretty much the same results.  COM1
works fine but COM4 (USB VCP) is still garbage.

On the bottom right, the indicators for 'BREAK' and 'Error' are both
red for COM4 but not for COM1.  Can somebody point me to more info on
what these mean or more documentation for Realterm?

Also, I receive 57 bytes at a time on COM1 (which is good) but 58
bytes on COM2 (which is bad).  And the HEX data is very different. 
I've tried writing the raw HEX out in binary to find some sync.
problem, but to no avail.

Any suggestions?

C Bremer wrote:

> Now I am trying to receive the same data via the USB port using a DLP
> Design DLP-USB232M USB Adapter.  I downloaded the Virtual Com Port
> (VCP) drivers and installed them.  The installed drivers show up in
> the device manager as "USB Serial Port (COM4)".  It is set to 4800,
> 8N1 under Properties.
>
> When I try to connect to COM4 in HyperTerminal, I only receive
> garbage.  The data displayed in the HyperTerminal window does not
> resemble the data seen from the connection on COM1 and is not the same
> length.
>
> I ran "Test Application V1.0" from DLP and when connected to COM1 it
> receives 113 bytes of data at a time.  When connected to COM4, 113
> bytes are also received.
>
> The DLP board is seated in a solderless breadboard.

<Egg suck>
Have you checked the signal levels to the DLP-USB232M, looking at them on a
scope? What RS232 level converter are you using?

</Egg suck>

As others have posted, I find that TeraTerm is much better for serial
communications debugging than HyperTerminal. portmon (www.sysinternals.com)
is very good for diagnosing problems too when you are writing the Windows
comms. code.

    Andrew

C Bremer wrote:
> "Leon Heller" <leon_heller@hotmail.com> wrote in message 
>> "C Bremer" <cdbremer@gmail.com> wrote in message
>>
>>> Hi.  I'm working on a project where I am connecting a Garmin OEM
>>> GPS Receiver (asynchronous, RX-TX-GND) through ...............
> 
>> Try RealTerm (it's free). It's much better than Hyperterminal for
>> sorting out comms problems.
> 
> I downloaded Realterm and I get pretty much the same results. 
> COM1 works fine but COM4 (USB VCP) is still garbage.
> 
> On the bottom right, the indicators for 'BREAK' and 'Error' are
> both red for COM4 but not for COM1.  Can somebody point me to more
> info on what these mean or more documentation for Realterm?
> 
> Also, I receive 57 bytes at a time on COM1 (which is good) but 58
> bytes on COM2 (which is bad).  And the HEX data is very different.
> I've tried writing the raw HEX out in binary to find some sync.
> problem, but to no avail.

Sounds like you have at least one of baudrate, parity, stop-bits
mis-set.

-- 
"If you want to post a followup via groups.google.com, don't use
 the broken "Reply" link at the bottom of the article.  Click on 
 "show options" at the top of the article, then click on the 
 "Reply" at the bottom of the article headers." - Keith Thompson

On 26 Feb, in article
     <9ec041b7.0502261936.72e68ed2@posting.google.com>
     cdbremer@gmail.com "C Bremer" wrote:

>"Leon Heller" <leon_heller@hotmail.com> wrote in message
> news:<42206ea7$0$2761$cc9e4d1f@news-text.dial.pipex.com>...
>> "C Bremer" <cdbremer@gmail.com> wrote in message 
>> news:9ec041b7.0502260348.3ad066e@posting.google.com...
>> > Hi.  I'm working on a project where I am connecting a Garmin OEM GPS
>> > Receiver (asynchronous, RX-TX-GND) through ...............
>
>> Try RealTerm (it's free). It's much better than Hyperterminal for sorting 
>> out comms problems.
>> 
>> Leon
>
>I downloaded Realterm and I get pretty much the same results.  COM1
>works fine but COM4 (USB VCP) is still garbage.
>
>On the bottom right, the indicators for 'BREAK' and 'Error' are both
>red for COM4 but not for COM1.  Can somebody point me to more info on
>what these mean or more documentation for Realterm?

Personally this suggests you have not interfaced to the RS232/USB
correctly as it looks like the signal is inverted somewhere, hence the
break condition.

>Also, I receive 57 bytes at a time on COM1 (which is good) but 58
>bytes on COM2 (which is bad).  And the HEX data is very different. 
>I've tried writing the raw HEX out in binary to find some sync.
>problem, but to no avail.
>
>Any suggestions?

How is the RS232 conversion done?
How is the serial data connected between your micro and the USB
adapter?

Suggests an inversion somewhere.

-- 
Paul Carpenter          | paul@pcserviceselectronics.co.uk
<http://www.pcserviceselectronics.co.uk/>    PC Services
<http://www.gnuh8.org.uk/>              GNU H8 & mailing list info
<http://www.badweb.org.uk/>             For those web sites you hate

paul$@pcserv.demon.co.uk (Paul Carpenter) wrote in message news:<20050227.1048.307069snz@pcserv.demon.co.uk>...
> On 26 Feb, in article
>      <9ec041b7.0502261936.72e68ed2@posting.google.com>
>      cdbremer@gmail.com "C Bremer" wrote:
> 
> >"Leon Heller" <leon_heller@hotmail.com> wrote in message
> > news:<42206ea7$0$2761$cc9e4d1f@news-text.dial.pipex.com>...
> >> "C Bremer" <cdbremer@gmail.com> wrote in message 
> >> news:9ec041b7.0502260348.3ad066e@posting.google.com...
> >> > Hi.  I'm working on a project where I am connecting a Garmin OEM GPS
> >> > Receiver (asynchronous, RX-TX-GND) through ...............
> >
> >> Try RealTerm (it's free). It's much better than Hyperterminal for sorting 
> >> out comms problems.
> >> 
> >> Leon
> >
> >I downloaded Realterm and I get pretty much the same results.  COM1
> >works fine but COM4 (USB VCP) is still garbage.
> >
> >On the bottom right, the indicators for 'BREAK' and 'Error' are both
> >red for COM4 but not for COM1.  Can somebody point me to more info on
> >what these mean or more documentation for Realterm?
> 
> Personally this suggests you have not interfaced to the RS232/USB
> correctly as it looks like the signal is inverted somewhere, hence the
> break condition.

Thank you.  This was exactly the problem.  The micro (GPS) output is
GND to 5V with the line idle output of the GPS being GND.  I inverted
the output of the GPS with a 74LS04 (overkill, I know) and now the
RS232/USB (FT232BM/DLP-USB232M) interface works great.
> 
> >Also, I receive 57 bytes at a time on COM1 (which is good) but 58
> >bytes on COM2 (which is bad).  And the HEX data is very different. 
> >I've tried writing the raw HEX out in binary to find some sync.
> >problem, but to no avail.
> >
> >Any suggestions?
> 
> How is the RS232 conversion done?
> How is the serial data connected between your micro and the USB
> adapter?
> 
> Suggests an inversion somewhere.