Shiftout not working!
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Has anybody used the UCN5818F which is a 32 channel source
latch/shift register? It is a three wire interface with two 16 bit
shift registers (see url http://www.allegromicro.com/sf/5818/)but
when I use the shiftout command similar to what I have done
successfully with the 74HC595 and a BS2, nothing happens.
Can anybody shed light on what is different between this chip and
the 74HC595.
many thanks in advance
Al
latch/shift register? It is a three wire interface with two 16 bit
shift registers (see url http://www.allegromicro.com/sf/5818/)but
when I use the shiftout command similar to what I have done
successfully with the 74HC595 and a BS2, nothing happens.
Can anybody shed light on what is different between this chip and
the 74HC595.
many thanks in advance
Al
Comments
things to check:
* Are you sending four bytes or two words?
-- If you send two words, you must use the \16 modifier after each variable
* Are you strobing the new data with low-high-low pulse on the Strobe pin?
* Is the Blanking pin (19) tied low? If this pin is high, all outputs are
off.
-- Jon Williams
-- Parallax
In a message dated 7/5/02 11:57:10 AM Central Daylight Time,
brownstamp@y... writes:
> Has anybody used the UCN5818F which is a 32 channel source
> latch/shift register? It is a three wire interface with two 16 bit
> shift registers (see url http://www.allegromicro.com/sf/5818/)but
> when I use the shiftout command similar to what I have done
> successfully with the 74HC595 and a BS2, nothing happens.
>
> Can anybody shed light on what is different between this chip and
> the 74HC595.
>
> many thanks in advance
>
> Al
>
[noparse][[/noparse]Non-text portions of this message have been removed]
what is the \16 modifier? I am sendind the following:
Shiftout DataP,Clock,msbfirst,[noparse][[/noparse]%11111111,%11111111,%11111111,
%11111111] ' to turn all pins on
pulseOut latch, 10
but nothing happen.
I did not have pin 19 tied low and will do so...this could be the
problem. Should I leave the Data Out pin floating or should I tied
it down as well?
I don't understand your comments about strobing. Should it be
different from the command above? if so, how would I do that?
Many many thanks in advance.
Al Najjar
FYI: this is for an exhibit at Sci-Port, a science center in
Shreveport, LA (close to you Jon) where kids arrange different
slices of Pizza in various fractional displays. It is lots of fun,
but I am using 5" common cathode 7-seg which is the reason for going
this route and not using the Max7219.
--- In basicstamps@y..., jonwms@a... wrote:
> I've not used this part, but I looked at the spec sheet. Here's a
couple of
> things to check:
>
> * Are you sending four bytes or two words?
> -- If you send two words, you must use the \16 modifier after
each variable
> * Are you strobing the new data with low-high-low pulse on the
Strobe pin?
> * Is the Blanking pin (19) tied low? If this pin is high, all
outputs are
> off.
>
> -- Jon Williams
> -- Parallax
>
>
> In a message dated 7/5/02 11:57:10 AM Central Daylight Time,
> brownstamp@y... writes:
>
>
> > Has anybody used the UCN5818F which is a 32 channel source
> > latch/shift register? It is a three wire interface with two 16
bit
> > shift registers (see url http://www.allegromicro.com/sf/5818/)
but
> > when I use the shiftout command similar to what I have done
> > successfully with the 74HC595 and a BS2, nothing happens.
> >
> > Can anybody shed light on what is different between this chip
and
> > the 74HC595.
> >
> > many thanks in advance
> >
> > Al
> >
>
>
>
>
> [noparse][[/noparse]Non-text portions of this message have been removed]
You could also do this:
SHIFTOUT Dpin, Cpin, MSBFirst, [noparse][[/noparse]aWord\16, bWord\16]
The \16 tells SHIFTOUT to send 16 bits. You can use any number between 1 and
16.
As far as your Latch goes, are you initializing it to Low before the code
runs? Remember that PULSOUT takes the pin to its opposite state for the
designated period, then puts it back. If you don't have this in your
initialization section, put it in:
LOW Latch
Let the Data Out pin float unless you decide to cascade devices.
Good luck with your project. We're always happy to hear [noparse][[/noparse]read] about Stamp
experiments designed to teach and inspire kids.
-- Jon Williams
-- Parallax
PS: Do you have enough current to drive all 32 loads or are you just checking
with a scope or logic probe?
In a message dated 7/5/02 4:39:59 PM Central Daylight Time,
brownstamp@y... writes:
> This make sense but I am still confused about the following:
>
> what is the \16 modifier? I am sendind the following:
> Shiftout DataP,Clock,msbfirst,[noparse][[/noparse]%11111111,%11111111,%11111111,
> %11111111] ' to turn all pins on
> pulseOut latch, 10
> but nothing happen.
> I did not have pin 19 tied low and will do so...this could be the
> problem. Should I leave the Data Out pin floating or should I tied
> it down as well?
>
> I don't understand your comments about strobing. Should it be
> different from the command above? if so, how would I do that?
>
> Many many thanks in advance.
>
>
> Al Najjar
> FYI: this is for an exhibit at Sci-Port, a science center in
> Shreveport, LA (close to you Jon) where kids arrange different
> slices of Pizza in various fractional displays. It is lots of fun,
> but I am using 5" common cathode 7-seg which is the reason for going
>
[noparse][[/noparse]Non-text portions of this message have been removed]
ps. I also have a model airplain in a large wind tunnel that is
completly controlled by one stamp: wind speed, aelerons, elevators
etc using joystick and throttle. We have over 20 stamps in use
throughout the center's exhibits.
Al
--- In basicstamps@y..., jonwms@a... wrote:
> By default, SHIFTOUT will spit out eight bits; unless you tell it
otherwise.
> You could also do this:
>
> SHIFTOUT Dpin, Cpin, MSBFirst, [noparse][[/noparse]aWord\16, bWord\16]
>
> The \16 tells SHIFTOUT to send 16 bits. You can use any number
between 1 and
> 16.
>
> As far as your Latch goes, are you initializing it to Low before
the code
> runs? Remember that PULSOUT takes the pin to its opposite state
for the
> designated period, then puts it back. If you don't have this in
your
> initialization section, put it in:
>
> LOW Latch
>
> Let the Data Out pin float unless you decide to cascade devices.
>
> Good luck with your project. We're always happy to hear [noparse][[/noparse]read]
about Stamp
> experiments designed to teach and inspire kids.
>
> -- Jon Williams
> -- Parallax
>
> PS: Do you have enough current to drive all 32 loads or are you
just checking
> with a scope or logic probe?
>
>
> In a message dated 7/5/02 4:39:59 PM Central Daylight Time,
> brownstamp@y... writes:
>
>
> > This make sense but I am still confused about the following:
> >
> > what is the \16 modifier? I am sendind the following:
> > Shiftout DataP,Clock,msbfirst,[noparse][[/noparse]%11111111,%11111111,%
11111111,
> > %11111111] ' to turn all pins on
> > pulseOut latch, 10
> > but nothing happen.
> > I did not have pin 19 tied low and will do so...this could be
the
> > problem. Should I leave the Data Out pin floating or should I
tied
> > it down as well?
> >
> > I don't understand your comments about strobing. Should it be
> > different from the command above? if so, how would I do that?
> >
> > Many many thanks in advance.
> >
> >
> > Al Najjar
> > FYI: this is for an exhibit at Sci-Port, a science center in
> > Shreveport, LA (close to you Jon) where kids arrange different
> > slices of Pizza in various fractional displays. It is lots of
fun,
> > but I am using 5" common cathode 7-seg which is the reason for
going
> >
>
>
>
>
> [noparse][[/noparse]Non-text portions of this message have been removed]