AVR-Chat

Can you use Reset for GPIO?  Possible in the ATTiny15, don't know about the
11.

----- Original Message -----
From: "Jose Fuentes" <josecarlosfuentes@yahoo.com.ar>
To: <AVR-Chat@yahoogroups.com>
Sent: Thursday, November 18, 2004 2:56 PM
Subject: Re: [AVR-Chat] SERIAL PORT IN ATTINY


>
> Thanks to everybody for the help!  I didn't realize
> that using a XTAL I have only one pin left.  Not sure
> but maybe would be better to use I2C to communicate
> because it doesn't require a XTAL.
>
> Regards,
> Jose
>
>
> > 8 pin chip, VCC, Gnd, X1, X2, TXD, RXD, Reset..  One
> > pin left.
>
>
>
>  --- Dave VanHorn <dvanhorn@dvanhorn.org> escribió:
> >
> > At 08:49 AM 11/18/2004, Jose Fuentes wrote:
> >
> >
> > >I want to use a Attiny11 (price under 0.54) and
> > >implement a serial port.  Since it doesn't have a
> > >USART I have to write the software to allow the
> > >microcontroller to send and receive data.  If
> > somebody
> > >has done something like this in assembly or C
> > please
> > >let me know.  Attiny11 only has 1KB FLASH and 32
> > >general purpose registers.
> > >Thanks.
> >
> > You may be a bit hosed here.
> > The T11's RC osc isn't calibrated, so you'd have to
> > use a resonator or xtal
> > at the cost of two pins.   If that works for you,
> > then set up an int at the
> > baud rate.
> >
> > Receive:
> > Put RXD on the hardware int pin (PB1)
> > When you see the start bit, set the timer to int you
> > in half a bit time.
> > When that int fires, sample the data. If still low,
> > you have a valid start
> > bit, and the next 8 timer ints simply sample and
> > shift.
> > If you want, you can pay attention to the stop bit,
> > one more int, should be
> > "idle".
> >
> > Transmit:
> > TXD on any pin.
> > Set the int to fire at the baud rate.
> > Send a start bit, 8 data, and one stop..
> >
> >
> > It's not that awful, but that means you have only
> > two more pins available
> > on the chip, and one of them is reset..
> >
> > 8 pin chip, VCC, Gnd, X1, X2, TXD, RXD, Reset..  One
> > pin left.
> >
> > Don't spend it all in one place!
> >
> >
> >
> >
> > ------------------------ Yahoo! Groups Sponsor
> >
> >
> >
> > Yahoo! Groups Links
> >
> >
> >     AVR-Chat-unsubscribe@yahoogroups.com
> >
> >
> >
> >
> >
> >
>
> Correo Yahoo! - 6 MB, tecnología antispam ¡gratis!
>  Suscribite ya http://correo.yahoo.com.ar/
>
>
>
>
> Yahoo! Groups Links
>
>
>
>
>
>
>