Serial VFD Problems
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I have a serial VFD display. It is supposed to operate @ 9600 n,8,1
baud. I'm trying to use it w/ my BS2 (it is TTL compatible), but I
can't get it to work. All I get is a bunch of garbage on the display.
There is info and a brief data sheet at:
http://www.dalewheat.com/projects/Serial%20VFD/
Please help if you can. Thank you.
-Brian Edmonson
baud. I'm trying to use it w/ my BS2 (it is TTL compatible), but I
can't get it to work. All I get is a bunch of garbage on the display.
There is info and a brief data sheet at:
http://www.dalewheat.com/projects/Serial%20VFD/
Please help if you can. Thank you.
-Brian Edmonson
Comments
baud. I'm trying to use it w/ my BS2 (it is TTL compatible), but I
can't get it to work. All I get is a bunch of garbage on the display.
There is info and a brief data sheet at:
http://www.dalewheat.com/projects/Serial%20VFD/
Please help if you can. Thank you.
-Brian Edmonson
I went through this with a crappy budget serial LCD and was getting the same
results. You need to know if it expects the serial line to be held low (at
ground) and swing up to 5 volts when data are sent (normal) or if it expects
the serial line to be held high (at 5 volts) and swing to ground when data
are sent (inverted). The Stamp will do either if you tell it to.You may also
need to have a pull-up or pull-down resistor on the serial line to keep the
line held in a constant state while the Stamp resets.
Look over the documentation and see if it mentions anything in particular.
Original Message
> I have a serial VFD display. It is supposed to operate @ 9600 n,8,1
> baud. I'm trying to use it w/ my BS2 (it is TTL compatible), but I
> can't get it to work. All I get is a bunch of garbage on the display.
> There is info and a brief data sheet at:
>
> http://www.dalewheat.com/projects/Serial%20VFD/
to see what results I'd get and it was the same garbage. I also
tried a pull up resistor w/o results but i didn't try a pull down
resistor. Thanks for your help.
-Brian
--- In basicstamps@yahoogroups.com, Rodent <daweasel@s...> wrote:
> Does the VFD expect a normal or inverted serial signal?
>
> I went through this with a crappy budget serial LCD and was
getting the same
> results. You need to know if it expects the serial line to be held
low (at
> ground) and swing up to 5 volts when data are sent (normal) or if
it expects
> the serial line to be held high (at 5 volts) and swing to ground
when data
> are sent (inverted). The Stamp will do either if you tell it
to.You may also
> need to have a pull-up or pull-down resistor on the serial line to
keep the
> line held in a constant state while the Stamp resets.
>
> Look over the documentation and see if it mentions anything in
particular.
>
>
Original Message
>
> > I have a serial VFD display. It is supposed to operate @ 9600
n,8,1
> > baud. I'm trying to use it w/ my BS2 (it is TTL compatible), but
I
> > can't get it to work. All I get is a bunch of garbage on the
display.
> > There is info and a brief data sheet at:
> >
> > http://www.dalewheat.com/projects/Serial%20VFD/
-Rob
Original Message
From: <be068095552@y...>
To: <basicstamps@yahoogroups.com>
Sent: Tuesday, February 25, 2003 9:31 PM
Subject: [noparse][[/noparse]basicstamps] Re: Serial VFD Problems
> I'm pretty sure that it wants an inverted signal. But, i tried both
> to see what results I'd get and it was the same garbage. I also
> tried a pull up resistor w/o results but i didn't try a pull down
> resistor. Thanks for your help.
>
> -Brian
>
>
>
>
> --- In basicstamps@yahoogroups.com, Rodent <daweasel@s...> wrote:
> > Does the VFD expect a normal or inverted serial signal?
> >
> > I went through this with a crappy budget serial LCD and was
> getting the same
> > results. You need to know if it expects the serial line to be held
> low (at
> > ground) and swing up to 5 volts when data are sent (normal) or if
> it expects
> > the serial line to be held high (at 5 volts) and swing to ground
> when data
> > are sent (inverted). The Stamp will do either if you tell it
> to.You may also
> > need to have a pull-up or pull-down resistor on the serial line to
> keep the
> > line held in a constant state while the Stamp resets.
> >
> > Look over the documentation and see if it mentions anything in
> particular.
> >
> >
Original Message
> >
> > > I have a serial VFD display. It is supposed to operate @ 9600
> n,8,1
> > > baud. I'm trying to use it w/ my BS2 (it is TTL compatible), but
> I
> > > can't get it to work. All I get is a bunch of garbage on the
> display.
> > > There is info and a brief data sheet at:
> > >
> > > http://www.dalewheat.com/projects/Serial%20VFD/
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>
circuit) for RS232 to TTL inverts the signal, so the TTL input may be
normal. Try a 10k pull-down resistor and normal SEROUT mode and see what
happens. Also, just to be on the safe side, I would put a 220 ohm resistor
between the Stamp pin and the TTL input. Keep the Stamp pin low for a good
2-3 seconds before trying to send any serial data.
Original Message
> I'm pretty sure that it wants an inverted signal. But, i tried both
> to see what results I'd get and it was the same garbage. I also
> tried a pull up resistor w/o results but i didn't try a pull down
> resistor. Thanks for your help.
> > Does the VFD expect a normal or inverted serial signal?
> >
> > I went through this with a crappy budget serial LCD and was
> getting the same
> > results. You need to know if it expects the serial line to be held
> low (at
> > ground) and swing up to 5 volts when data are sent (normal) or if
> it expects
> > the serial line to be held high (at 5 volts) and swing to ground
> when data
> > are sent (inverted). The Stamp will do either if you tell it
> to.You may also
> > need to have a pull-up or pull-down resistor on the serial line to
> keep the
> > line held in a constant state while the Stamp resets.
> >
> > Look over the documentation and see if it mentions anything in
> particular.
> >
> >
Original Message
> >
> > > I have a serial VFD display. It is supposed to operate @ 9600
> n,8,1
> > > baud. I'm trying to use it w/ my BS2 (it is TTL compatible), but
> I
> > > can't get it to work. All I get is a bunch of garbage on the
> display.
> > > There is info and a brief data sheet at:
> > >
> > > http://www.dalewheat.com/projects/Serial%20VFD/
wrote:
> Can you post the "serout" command you used.
>
> -Rob
>
>
Original Message
> From: <be068095552@y...>
> To: <basicstamps@yahoogroups.com>
> Sent: Tuesday, February 25, 2003 9:31 PM
> Subject: [noparse][[/noparse]basicstamps] Re: Serial VFD Problems
>
>
> > I'm pretty sure that it wants an inverted signal. But, i tried
both
> > to see what results I'd get and it was the same garbage. I also
> > tried a pull up resistor w/o results but i didn't try a pull down
> > resistor. Thanks for your help.
> >
> > -Brian
> >
> >
> >
> >
> > --- In basicstamps@yahoogroups.com, Rodent <daweasel@s...> wrote:
> > > Does the VFD expect a normal or inverted serial signal?
> > >
> > > I went through this with a crappy budget serial LCD and was
> > getting the same
> > > results. You need to know if it expects the serial line to be
held
> > low (at
> > > ground) and swing up to 5 volts when data are sent (normal) or
if
> > it expects
> > > the serial line to be held high (at 5 volts) and swing to
ground
> > when data
> > > are sent (inverted). The Stamp will do either if you tell it
> > to.You may also
> > > need to have a pull-up or pull-down resistor on the serial
line to
> > keep the
> > > line held in a constant state while the Stamp resets.
> > >
> > > Look over the documentation and see if it mentions anything in
> > particular.
> > >
> > >
Original Message
> > >
> > > > I have a serial VFD display. It is supposed to operate @
9600
> > n,8,1
> > > > baud. I'm trying to use it w/ my BS2 (it is TTL compatible),
but
> > I
> > > > can't get it to work. All I get is a bunch of garbage on the
> > display.
> > > > There is info and a brief data sheet at:
> > > >
> > > > http://www.dalewheat.com/projects/Serial%20VFD/
> >
> >
> > To UNSUBSCRIBE, just send mail to:
> > basicstamps-unsubscribe@yahoogroups.com
> > from the same email address that you subscribed. Text in the
Subject and
> Body of the message will be ignored.
> >
> >
> > Your use of Yahoo! Groups is subject to
http://docs.yahoo.com/info/terms/
> >
> >
> >
just fried the serial controller circuit. I accidentally reversed
the +V and GND and it is history. This bites! Thats my luck for ya.
Oh well, back to parallel inputs. :-( (good thing it wasn't brand
new).
-Brian Edmonson
I now double-triple-check my work before I apply power.
Original Message
> Thanks to everybody for your help, but I think we can quit now. I
> just fried the serial controller circuit. I accidentally reversed
> the +V and GND and it is history. This bites! Thats my luck for ya.
> Oh well, back to parallel inputs. :-( (good thing it wasn't brand
> new).