Is there any form of IRQ with the Stamp?
Hello,
Does the BS2 have any form of an IRQ? I can't seem to
find it. If not, is there anything that closely
resembles the functionality of an IRQ in the
programming of a BS2?
Thanks,
Todd
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Does the BS2 have any form of an IRQ? I can't seem to
find it. If not, is there anything that closely
resembles the functionality of an IRQ in the
programming of a BS2?
Thanks,
Todd
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Do You Yahoo!?
Yahoo! Messenger - Talk while you surf! It's FREE.
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Comments
>Hello,
>
>Does the BS2 have any form of an IRQ? I can't seem to
>find it. If not, is there anything that closely
>resembles the functionality of an IRQ in the
>programming of a BS2?
Hi Todd -
Simply put - no. Polling is generally used in lieu of interrupts.
Multiplexed inputs are sometimes used, where appropriate, for multiple ADC
inputs. So too, parallel to serial shift registers - see Shiftin and
Shiftout in the manual.
>Thanks,
>
>Todd
Regards,
Bruce Bates
>__________________________________________________
>Do You Yahoo!?
>Yahoo! Messenger - Talk while you surf! It's FREE.
>http://im.yahoo.com/
> Hello,
>
> Does the BS2 have any form of an IRQ? I can't seem to
> find it. If not, is there anything that closely
> resembles the functionality of an IRQ in the
> programming of a BS2?
If you don't have IRQ, you have to resort to device polling.
Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma - Bremerton
email: lamont@a... WWW: http://www.serv.net
"...There's no moral, it's just a lot of stuff that happens". - H. Simpson
I haven't done this, but the LOSA mentions someone using the RESET pin as a
form of interrupt. I haven't looked at it, but this would likely require a
differentiator (in other words, a capacitor so you just get a pulse on the
reset) and a latch connected to an input pin.
On reset, you look at the latch. If it is 0, you just got reset. If it is 1,
you just got interrupted. Of course, you can't return from the interrupt in
any real sense. But you can service an external event and the go on with
what you normally do. The LOSA is at -- I think -- www.hth.com/losa.
Why not tell us _what_ you want to do and maybe someone can come up with an
alternative to an IRQ.
Regards,
Al Williams
AWC
*Floating point math for the Stamp, PIC, SX, or any microcontroller:
http://www.al-williams.com/awce/pak1.htm
>
Original Message
> From: Todd Botner [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=nYzHhwoVAPt2Jr9_rPNiXH46z8Gk6aQ6T9eJzB3FOcE0rM61xbSsF-oF34fZaCAQXZbbprTpPUG2_UW0UAm0-g]contacttodd@y...[/url
> Sent: Monday, October 30, 2000 10:43 PM
> To: basicstamps@egroups.com
> Subject: [noparse][[/noparse]basicstamps] Is there any form of IRQ with the Stamp?
>
>
> Hello,
>
> Does the BS2 have any form of an IRQ? I can't seem to
> find it. If not, is there anything that closely
> resembles the functionality of an IRQ in the
> programming of a BS2?
>
> Thanks,
>
> Todd
>
> __________________________________________________
> Do You Yahoo!?
> Yahoo! Messenger - Talk while you surf! It's FREE.
> http://im.yahoo.com/
>
>
Just finished a project where I used the technique Al mentioned. It isn't
fast, but seems to be fairly consistent. I used a oneshot on the input
because I needed the "event" to be controlled by the precise timing of the
oneshot and couldn't wait to setup a PULSOUT. Of course, you loose
everything "in process" and you need to make sure that your hardware
initialization routines put all of your I/O pins where you need them. It
isn't a replacement for an interrupt, but in my case, it got the job done.
Mike
At 07:25 AM 10/31/00 -0600, you wrote:
>Hi Todd,
>
>I haven't done this, but the LOSA mentions someone using the RESET pin as a
>form of interrupt. I haven't looked at it, but this would likely require a
>differentiator (in other words, a capacitor so you just get a pulse on the
>reset) and a latch connected to an input pin.
>
>On reset, you look at the latch. If it is 0, you just got reset. If it is 1,
>you just got interrupted. Of course, you can't return from the interrupt in
>any real sense. But you can service an external event and the go on with
>what you normally do. The LOSA is at -- I think -- www.hth.com/losa.