Problem with COM1 and COM3

Started by simone_zecchetto September 25, 2006
Hi to all, great group.
I've got the bx24 since 2002.
Now I use this chip for inquiring an OEM GPS and send the NMEA
sentence to a GSM modem. All it works dearly if I use COM3 for both
the apps.
But I don't want to define and redefine com3 every time I look at the
GPS and at the GSM (the baudrates isn't equal).
'Call DefineCom3 etc.....
'Call opencom(3, 4800, inputbuffer, outputbuffer)
With 'jumping' com3 the modem works, it receive every command and it
sends sms etc...

I try to connect COM1 at the GSM modem but this don't work.
'Call opencom(1, 19200, inputbuffer, outputbuffer).

The modem doesn't respond
I use the serial bas routines.

Nobody is may gives me any suggestions?
Excuse me for my bad bad english.
Cheers zec.
> 'Call DefineCom3 etc...

Do you use inverted logic for the GSM modem? You have the option with
COM3 to use either logic sense, but COM1 has hardware inverters on RX
and TX to be TTL-serial compatible with RS232. Perhaps you need to
re-invert COM1.
Tom
--- In b..., "Tom Becker" wrote:
>
> > 'Call DefineCom3 etc...
>
> Do you use inverted logic for the GSM modem? You have the option with
> COM3 to use either logic sense, but COM1 has hardware inverters on RX
> and TX to be TTL-serial compatible with RS232. Perhaps you need to
> re-invert COM1.
> Tom
>
Uao great man!!!
I'm a newby.
I use a maxim 232 for converting TC-35 (gps modem) tx rx signal into
TTL bx24 compatible rx tx. Do you mean that i can connect tc-35 rx tx
directly to the pins 1 and 2 of the bx24?
Thank You thousands.
zec
> ... connect tc-35 rx tx directly to the pins 1 and 2 of the bx24?

The TC-35 looks like it has a female DB9, so I'd try TC-35 pin 2 to
BX-24 pin 1, TC-35 pin 3 to BX-24 pin 2, and TC-35 pin 5 to BX-24 pin
4. Or, if you have a DB9 on your BX-24, just use a null modem cable
between the two devices.

Ciao! Abitato a Saluzzo molti anni fa.
Tom
> ... connect tc-35 rx tx directly to the pins 1 and 2 of the bx24?

The TC-35 looks like it has a female DB9, so I'd try TC-35 pin 2 to
BX-24 pin 1, TC-35 pin 3 to BX-24 pin 2, and TC-35 pin 5 to BX-24 pin 4.
Or, if you have a DB9 on your BX-24, just use a null modem cable
between the two devices.

Ciao! Abitato a Saluzzo molti anni fa.
Tom
--- In b..., "Tom Becker" wrote:
>
> > ... connect tc-35 rx tx directly to the pins 1 and 2 of the bx24?
>
> The TC-35 looks like it has a female DB9, so I'd try TC-35 pin 2 to
> BX-24 pin 1, TC-35 pin 3 to BX-24 pin 2, and TC-35 pin 5 to BX-24 pin
> 4. Or, if you have a DB9 on your BX-24, just use a null modem cable
> between the two devices.
>
> Ciao! Abitato a Saluzzo molti anni fa.
> Tom
>
Great, Now all works.
Thank You man.
Saluzzo? Near Cuneo, I've got some friends of mine living there.
I live in Verona, the city of Romeo & Juliet.
Cheers tom