Charter of newsgroup

FreeRTOS.org wrote:
> > There is no pic newsgroup. Some poorly-run servers carry a spurious
> > piclist newsgroup (gated to a mailing list?) that has not been
> > created according to the Big-8 procedures, and is not propagated
> > by well-configured servers.
>
> As per:
> http://groups.google.com/group/comp.arch.embedded.piclist

Microchip also maintains a friendly set of fora on their own website,
almost as easy to use as a newsgroup.

http://forum.microchip.com/

martin griffith wrote:
> On 29 Aug 2006 13:10:10 -0700, in comp.arch.embedded
> "pomerado@hotmail.com" <pomerado@hotmail.com> wrote:
>
> >
> >Al wrote:
> >> Is this an appropriate newsgroup to submit questions regarding PICs?
> >>
> >> I haven't been able to find any newsgroups listed as such that are
> >> provided by my ISP.
> try piclist.com, seems to be recommended, but since I dont like
> pics.......
> >
> >No.  This is the 555 newsgroup.
>
> nope  that is definately sci.electronics design :-)

Oops.  Lost track of where I was.

On 29 Aug 2006 16:00:17 -0700, in comp.arch.embedded
"pomerado@hotmail.com" <pomerado@hotmail.com> wrote:

>
>FreeRTOS.org wrote:
>> > There is no pic newsgroup. Some poorly-run servers carry a spurious
>> > piclist newsgroup (gated to a mailing list?) that has not been
>> > created according to the Big-8 procedures, and is not propagated
>> > by well-configured servers.
>>
>> As per:
>> http://groups.google.com/group/comp.arch.embedded.piclist
>
>Microchip also maintains a friendly set of fora on their own website,
>almost as easy to use as a newsgroup.

are pics as easy to use as a newsgroup?

<duck>


martin

In article <1156882054.604376.170200@m79g2000cwm.googlegroups.com>,
 "linnix" <me@linnix.info-for.us> wrote:

> > > Is this an appropriate newsgroup to submit questions regarding PICs?
> > >
> > > I haven't been able to find any newsgroups listed as such that are
> > > provided by my ISP.
> > >
> > > Al
> >
> > Definitely.  This is the place.
> 
> Only if you are willing to ask the same question in an auditorium full
> of 500 experienced engineers.
> 

OK, thanks. I'm overwhelmed by the response.

First question.

I want to use a real time clock for my application. I want to make the 
thing as cheaply as possible so I am looking for the lowlyest (??) PIC I 
can use. I have my sights set on the 12C508A. 

What I want to do is use two pins for the RT clock, two for controlling 
an external device, and two for communicating with the PIC from an 
external terminal service, yet to be determined.

I know I may not have enough program space to do this, but I'm just 
starting.

At any rate, what I want to know is this. A real time clock chip like 
the NJU6355 has three pins, CE, a clock and a data I/O. Can I do a 
hardware CE and still have full functionality of the RT clock using just 
the clock and I/O pins?

As you can see, I run out of PIC pins if I can't.

Al

In comp.arch.embedded,
Al <no.spam@wanted.com> wrote:
>
> At any rate, what I want to know is this. A real time clock chip like 
> the NJU6355 has three pins, CE, a clock and a data I/O. Can I do a 
> hardware CE and still have full functionality of the RT clock using just 
> the clock and I/O pins?
>
> As you can see, I run out of PIC pins if I can't.
>
I can't tell you if it will work, but i'm doubtfull. If it doesn't,
you can always think about using an I2C RTC like the PCF8593, which
only requires 2 pins.

-- 
Stef    (remove caps, dashes and .invalid from e-mail address to reply by mail)

In article <56770$44f59823$54f63171$22626@publishnet.news-service.com>,
 Stef <stef33d@yahooI-N-V-A-L-I-D.com.invalid> wrote:

> In comp.arch.embedded,
> Al <no.spam@wanted.com> wrote:
> >
> > At any rate, what I want to know is this. A real time clock chip like 
> > the NJU6355 has three pins, CE, a clock and a data I/O. Can I do a 
> > hardware CE and still have full functionality of the RT clock using just 
> > the clock and I/O pins?
> >
> > As you can see, I run out of PIC pins if I can't.
> >
> I can't tell you if it will work, but i'm doubtfull. If it doesn't,
> you can always think about using an I2C RTC like the PCF8593, which
> only requires 2 pins.

I2C would be nice but it requires a license from Phillips as I 
understand it for commercial use.

Al

In comp.arch.embedded,
Al <no.spam@wanted.com> wrote:
> In article <56770$44f59823$54f63171$22626@publishnet.news-service.com>,
>  Stef <stef33d@yahooI-N-V-A-L-I-D.com.invalid> wrote:
>
>> In comp.arch.embedded,
>> Al <no.spam@wanted.com> wrote:
>> >
>> > At any rate, what I want to know is this. A real time clock chip like 
>> > the NJU6355 has three pins, CE, a clock and a data I/O. Can I do a 
>> > hardware CE and still have full functionality of the RT clock using just 
>> > the clock and I/O pins?
>> >
>> > As you can see, I run out of PIC pins if I can't.
>> >
>> I can't tell you if it will work, but i'm doubtfull. If it doesn't,
>> you can always think about using an I2C RTC like the PCF8593, which
>> only requires 2 pins.
>
> I2C would be nice but it requires a license from Phillips as I 
> understand it for commercial use.
>
If you are a chip vendor that sells IC's which have I2C in the datasheet
then you need a licence. Many chip vendors go around this by calling their
interface TWI (Two Wire Interface), which is in fact I2C.

If you are only using the I2C chips, you don't need a license. Maybe if you
advertise the I2C on the outside of the box, but why should you?

-- 
Stef    (remove caps, dashes and .invalid from e-mail address to reply by mail)

Al wrote:
> In article <1156882054.604376.170200@m79g2000cwm.googlegroups.com>,
>  "linnix" <me@linnix.info-for.us> wrote:
>
> > > > Is this an appropriate newsgroup to submit questions regarding PICs?
> > > >
> > > > I haven't been able to find any newsgroups listed as such that are
> > > > provided by my ISP.
> > > >
> > > > Al
> > >
> > > Definitely.  This is the place.
> >
> > Only if you are willing to ask the same question in an auditorium full
> > of 500 experienced engineers.
> >
>
> OK, thanks. I'm overwhelmed by the response.
>
> First question.
>
> I want to use a real time clock for my application. I want to make the
> thing as cheaply as possible so I am looking for the lowlyest (??) PIC I
> can use. I have my sights set on the 12C508A.
>
> What I want to do is use two pins for the RT clock, two for controlling
> an external device, and two for communicating with the PIC from an
> external terminal service, yet to be determined.
>
> I know I may not have enough program space to do this, but I'm just
> starting.
>
> At any rate, what I want to know is this. A real time clock chip like
> the NJU6355 has three pins, CE, a clock and a data I/O. Can I do a
> hardware CE and still have full functionality of the RT clock using just
> the clock and I/O pins?

What would your hardware CE be?  It must determine the I/O direction
for the PIC to handle it properly.  By the way, why can't you implement
the RTC inside the PIC?

> 
> As you can see, I run out of PIC pins if I can't.
> 
> Al

In article <1156979843.522090.281930@h48g2000cwc.googlegroups.com>,
 "linnix" <me@linnix.info-for.us> wrote:

> Al wrote:
> > In article <1156882054.604376.170200@m79g2000cwm.googlegroups.com>,
> >  "linnix" <me@linnix.info-for.us> wrote:
> >
> > > > > Is this an appropriate newsgroup to submit questions regarding PICs?
> > > > >
> > > > > I haven't been able to find any newsgroups listed as such that are
> > > > > provided by my ISP.
> > > > >
> > > > > Al
> > > >
> > > > Definitely.  This is the place.
> > >
> > > Only if you are willing to ask the same question in an auditorium full
> > > of 500 experienced engineers.
> > >
> >
> > OK, thanks. I'm overwhelmed by the response.
> >
> > First question.
> >
> > I want to use a real time clock for my application. I want to make the
> > thing as cheaply as possible so I am looking for the lowlyest (??) PIC I
> > can use. I have my sights set on the 12C508A.
> >
> > What I want to do is use two pins for the RT clock, two for controlling
> > an external device, and two for communicating with the PIC from an
> > external terminal service, yet to be determined.
> >
> > I know I may not have enough program space to do this, but I'm just
> > starting.
> >
> > At any rate, what I want to know is this. A real time clock chip like
> > the NJU6355 has three pins, CE, a clock and a data I/O. Can I do a
> > hardware CE and still have full functionality of the RT clock using just
> > the clock and I/O pins?
> 
> What would your hardware CE be?  It must determine the I/O direction
> for the PIC to handle it properly.  By the way, why can't you implement
> the RTC inside the PIC?
> 
> > 
> > As you can see, I run out of PIC pins if I can't.
> > 
> > Al
> 

According to the spec for the RTC, CE HIGH means that I/O is available 
and nothing else. So, as I think about it more, I think that I can just 
set it HIGH and as long as I am not querying the RTC, I should be 
getting nothing out. And if I ask for the day of the week, I should get 
that data out.

I'm not attempting to do RTC inside the PIC as I want to use the 
cheapest one available, like the 12C508A. And why reinvent the wheel.

Al

Al wrote:
> In article <1156979843.522090.281930@h48g2000cwc.googlegroups.com>,
>  "linnix" <me@linnix.info-for.us> wrote:
>
> > Al wrote:
> > > In article <1156882054.604376.170200@m79g2000cwm.googlegroups.com>,
> > >  "linnix" <me@linnix.info-for.us> wrote:
> > >
> > > > > > Is this an appropriate newsgroup to submit questions regarding PICs?
> > > > > >
> > > > > > I haven't been able to find any newsgroups listed as such that are
> > > > > > provided by my ISP.
> > > > > >
> > > > > > Al
> > > > >
> > > > > Definitely.  This is the place.
> > > >
> > > > Only if you are willing to ask the same question in an auditorium full
> > > > of 500 experienced engineers.
> > > >
> > >
> > > OK, thanks. I'm overwhelmed by the response.
> > >
> > > First question.
> > >
> > > I want to use a real time clock for my application. I want to make the
> > > thing as cheaply as possible so I am looking for the lowlyest (??) PIC I
> > > can use. I have my sights set on the 12C508A.
> > >
> > > What I want to do is use two pins for the RT clock, two for controlling
> > > an external device, and two for communicating with the PIC from an
> > > external terminal service, yet to be determined.
> > >
> > > I know I may not have enough program space to do this, but I'm just
> > > starting.
> > >
> > > At any rate, what I want to know is this. A real time clock chip like
> > > the NJU6355 has three pins, CE, a clock and a data I/O. Can I do a
> > > hardware CE and still have full functionality of the RT clock using just
> > > the clock and I/O pins?
> >
> > What would your hardware CE be?  It must determine the I/O direction
> > for the PIC to handle it properly.  By the way, why can't you implement
> > the RTC inside the PIC?
> >
> > >
> > > As you can see, I run out of PIC pins if I can't.
> > >
> > > Al
> >
>
> According to the spec for the RTC, CE HIGH means that I/O is available
> and nothing else. So, as I think about it more, I think that I can just
> set it HIGH and as long as I am not querying the RTC, I should be
> getting nothing out. And if I ask for the day of the week, I should get
> that data out.

I could be wrong, but CE determine the direction of the DATA pin.
Forgive me if I read the spec incorrectly.

>
> I'm not attempting to do RTC inside the PIC as I want to use the
> cheapest one available, like the 12C508A. And why reinvent the wheel.

There are plenty of software library to implement a clock in PIC, which
would cut the cost (and the RTC chip).  You don't have to reinvent it.

> 
> Al