i''m new, need help with command
Archiver
Posts: 46,084
No, it will not hurt the Stamp; it will simply consume more current.
-- Jon Williams
-- Applications Engineer, Parallax
-- Dallas Office
Original Message
From: andy_watson5 [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=BE9tjQK5fTSezXhS4Hl4epJjFFtoYRiOsfOwN7sh4l_9B8pbf5dAHksaLsM0QHF8hfo4nL7ZdcwF3g7S]andywatson@m...[/url
Sent: Tuesday, February 10, 2004 12:57 PM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] Re: i'm new, need help with command
You bring up a good point. When I read Jon's pdf file he linked a
couple messages ago, I saw that POLLWAIT would let the stamp "nap"
until a polled event happens. If I don't do the polling option and
just run the small continuous loop looking for a switch input, is
there anything wrong with leaving the stamp in 'full power' mode?
This won't be on battery power, so I'm not concerned with drawing
down a battery or anything. Would it hurt the stamp to stay active
all the time and not go into the nap mode?
Thanks
--- In basicstamps@yahoogroups.com, Tracy Allen <tracy@e...> wrote:
> Hi again Andy,
>
> Yes, that straight out scan is going to be simpler than the mind
set
> for the POLLing commands. And yes, 0.5 second is forever in
> microcomputer terms. On the Stamp, each one of those instructions
> like
> > > IF (ButtonA = 1) THEN BtnA_Sub
> will take about 1 millisecond to execute, so the entire loop to
scan
> 4 pushbuttons will execute in well under 10 milliseconds.
>
> Note that you also have to allow for the case that someone leans on
> one of the buttons. If you don't want the button action to occur
over
> and over, you will have to write code to do the action once per
> event. Take a look at the BUTTON command, which has such
debounce.
> However, everyone agrees that with several buttons involved it is
> more efficient & flexible to write your own code to do that.
>
> The simple scanning will be more of a problem if the Stamp has to
do
> a lot of other processing at the same time, or if you want it to
> catch a quick 0.05 second button press or a similar signal that
comes
> from an instrument like a tipping bucket rain gage. Or, if the
> program has to conserve power while waiting for a button to be
> pressed. The POLLIN latched modes work really well with the
POLLWAIT
> command on the BS2pe/pe, so the chip can nap until an event happens
> and then test the scratchpad registers to determine which event(s).
>
> You mentioned an RC input network. That can effectively stretch
> events like the 30 millisecond rain gage pulse. Just a 0.1uf
> capacitor from the Stamp input to ground, and 270 ohm resistors to
> limit the current to the stamp pin and to the switch. The stamp
pin
> is an output to charge the capacitor. The program returns about
once
> a second to check the voltage on the pin and to refresh it. If it
> finds zero volts, that means the switch has closed in the interim.
> The Stamp adds one to the count before refreshing the charge on the
> capacitor.
>
> -- Tracy
>
>
>
>
>
> >Well, by "quick", I mean that the pin will only be high for maybe
0.5
> >seconds. Assuming that the only thing going is the loop looking
for
> >a high on one of the 4 pins, I don't know if that 0.5 sec high is
> >long enough. Perhaps I could add some kind of RC circuit to keep
the
> >pin latched for an extra second or so. The POLLMODE latching stuff
> >looks a little more complicated. But if it's that much better,
I'll
> >try to figure it out.
> >
> >Thanks,
> >Andy
> >
> >--- In basicstamps@yahoogroups.com, "Jon Williams" <jwilliams@p...>
> >wrote:
> >> The depends on how you define "quick" and keep in mind that
standard
> >> Stamp inputs are not latched. As Tracy suggested, however, you
can
> >use
> >> POLLIN instruction with a MODE that will latch polled inputs,
but
> >note
> >> that using POLL instructions work in between other things (the
> >Stamp is
> >> single threaded). In addition to the manual, and information on
> >Tracy's
> >> web site, you may find this article helpful:
> >>
> >> http://www.parallax.com/dl/docs/cols/nv/vol2/col/69.pdf
> >>
> >> -- Jon Williams
> >> -- Applications Engineer, Parallax
> >> -- Dallas Office
> >>
>
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.
Yahoo! Groups Links
This message has been scanned by WebShield. Please report SPAM to
abuse@p....
-- Jon Williams
-- Applications Engineer, Parallax
-- Dallas Office
Original Message
From: andy_watson5 [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=BE9tjQK5fTSezXhS4Hl4epJjFFtoYRiOsfOwN7sh4l_9B8pbf5dAHksaLsM0QHF8hfo4nL7ZdcwF3g7S]andywatson@m...[/url
Sent: Tuesday, February 10, 2004 12:57 PM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] Re: i'm new, need help with command
You bring up a good point. When I read Jon's pdf file he linked a
couple messages ago, I saw that POLLWAIT would let the stamp "nap"
until a polled event happens. If I don't do the polling option and
just run the small continuous loop looking for a switch input, is
there anything wrong with leaving the stamp in 'full power' mode?
This won't be on battery power, so I'm not concerned with drawing
down a battery or anything. Would it hurt the stamp to stay active
all the time and not go into the nap mode?
Thanks
--- In basicstamps@yahoogroups.com, Tracy Allen <tracy@e...> wrote:
> Hi again Andy,
>
> Yes, that straight out scan is going to be simpler than the mind
set
> for the POLLing commands. And yes, 0.5 second is forever in
> microcomputer terms. On the Stamp, each one of those instructions
> like
> > > IF (ButtonA = 1) THEN BtnA_Sub
> will take about 1 millisecond to execute, so the entire loop to
scan
> 4 pushbuttons will execute in well under 10 milliseconds.
>
> Note that you also have to allow for the case that someone leans on
> one of the buttons. If you don't want the button action to occur
over
> and over, you will have to write code to do the action once per
> event. Take a look at the BUTTON command, which has such
debounce.
> However, everyone agrees that with several buttons involved it is
> more efficient & flexible to write your own code to do that.
>
> The simple scanning will be more of a problem if the Stamp has to
do
> a lot of other processing at the same time, or if you want it to
> catch a quick 0.05 second button press or a similar signal that
comes
> from an instrument like a tipping bucket rain gage. Or, if the
> program has to conserve power while waiting for a button to be
> pressed. The POLLIN latched modes work really well with the
POLLWAIT
> command on the BS2pe/pe, so the chip can nap until an event happens
> and then test the scratchpad registers to determine which event(s).
>
> You mentioned an RC input network. That can effectively stretch
> events like the 30 millisecond rain gage pulse. Just a 0.1uf
> capacitor from the Stamp input to ground, and 270 ohm resistors to
> limit the current to the stamp pin and to the switch. The stamp
pin
> is an output to charge the capacitor. The program returns about
once
> a second to check the voltage on the pin and to refresh it. If it
> finds zero volts, that means the switch has closed in the interim.
> The Stamp adds one to the count before refreshing the charge on the
> capacitor.
>
> -- Tracy
>
>
>
>
>
> >Well, by "quick", I mean that the pin will only be high for maybe
0.5
> >seconds. Assuming that the only thing going is the loop looking
for
> >a high on one of the 4 pins, I don't know if that 0.5 sec high is
> >long enough. Perhaps I could add some kind of RC circuit to keep
the
> >pin latched for an extra second or so. The POLLMODE latching stuff
> >looks a little more complicated. But if it's that much better,
I'll
> >try to figure it out.
> >
> >Thanks,
> >Andy
> >
> >--- In basicstamps@yahoogroups.com, "Jon Williams" <jwilliams@p...>
> >wrote:
> >> The depends on how you define "quick" and keep in mind that
standard
> >> Stamp inputs are not latched. As Tracy suggested, however, you
can
> >use
> >> POLLIN instruction with a MODE that will latch polled inputs,
but
> >note
> >> that using POLL instructions work in between other things (the
> >Stamp is
> >> single threaded). In addition to the manual, and information on
> >Tracy's
> >> web site, you may find this article helpful:
> >>
> >> http://www.parallax.com/dl/docs/cols/nv/vol2/col/69.pdf
> >>
> >> -- Jon Williams
> >> -- Applications Engineer, Parallax
> >> -- Dallas Office
> >>
>
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.
Yahoo! Groups Links
This message has been scanned by WebShield. Please report SPAM to
abuse@p....