Is it possible to implement UART by GPIO?

let GPIO high or low by timer interrupt to emulate time sequence of UART
transfer and receive, is it possible?

mobilevil
Tue Jan 11 06:57:06 CST 2005

it is possible. we did it with 8051. but it will consume a lot of cpu power.
"chanter" <blueenc@hotmail.com> wrote in message
news:OlXCWS99EHA.2180@TK2MSFTNGP12.phx.gbl...
> let GPIO high or low by timer interrupt to emulate time sequence of UART
> transfer and receive, is it possible?
>
>
>

chanter
Tue Jan 11 07:09:28 CST 2005

I forget to say my os is wince and pxa255 platform.I think it's possible
with 8051 just because it's not a mutli-task system.but under wince,it take
much more time from interrupt generation to my driver reading and
writing.and at this time ,maybe there are other interrupt to handle such as
keyboard,mouse..
"mobilevil" <kccheng@kachun-uknowwhat.com> дÈëÏûÏ¢ÐÂÎÅ
:#djez099EHA.2016@TK2MSFTNGP15.phx.gbl...
> it is possible. we did it with 8051. but it will consume a lot of cpu
power.
> "chanter" <blueenc@hotmail.com> wrote in message
> news:OlXCWS99EHA.2180@TK2MSFTNGP12.phx.gbl...
> > let GPIO high or low by timer interrupt to emulate time sequence of UART
> > transfer and receive, is it possible?
> >
> >
> >
>
>

voidcoder
Tue Jan 11 07:24:44 CST 2005

Why don't use one of 3 available UARTs?


"chanter" <jsun98@163.com> wrote in message
news:u#2y1799EHA.2984@TK2MSFTNGP09.phx.gbl...
> I forget to say my os is wince and pxa255 platform.I think it's possible
> with 8051 just because it's not a mutli-task system.but under wince,it
take
> much more time from interrupt generation to my driver reading and
> writing.and at this time ,maybe there are other interrupt to handle such
as
> keyboard,mouse..
> "mobilevil" <kccheng@kachun-uknowwhat.com> дÈëÏûÏ¢ÐÂÎÅ
> :#djez099EHA.2016@TK2MSFTNGP15.phx.gbl...
> > it is possible. we did it with 8051. but it will consume a lot of cpu
> power.
> > "chanter" <blueenc@hotmail.com> wrote in message
> > news:OlXCWS99EHA.2180@TK2MSFTNGP12.phx.gbl...
> > > let GPIO high or low by timer interrupt to emulate time sequence of
UART
> > > transfer and receive, is it possible?
> > >
> > >
> > >
> >
> >
>
>

Chanter
Tue Jan 11 08:00:28 CST 2005

I need to communicate with 8051 uart(mode3: 9 bit data,1 bit stop£©,but
pxa255 uart not support 9 bit data.

"voidcoder" <voidcoder@yahoo.com> wrote in message
news:e64cTD#9EHA.3336@TK2MSFTNGP11.phx.gbl...
> Why don't use one of 3 available UARTs?
>
>
> "chanter" <jsun98@163.com> wrote in message
> news:u#2y1799EHA.2984@TK2MSFTNGP09.phx.gbl...
> > I forget to say my os is wince and pxa255 platform.I think it's possible
> > with 8051 just because it's not a mutli-task system.but under wince,it
> take
> > much more time from interrupt generation to my driver reading and
> > writing.and at this time ,maybe there are other interrupt to handle such
> as
> > keyboard,mouse..
> > "mobilevil" <kccheng@kachun-uknowwhat.com> дÈëÏûÏ¢ÐÂÎÅ
> > :#djez099EHA.2016@TK2MSFTNGP15.phx.gbl...
> > > it is possible. we did it with 8051. but it will consume a lot of cpu
> > power.
> > > "chanter" <blueenc@hotmail.com> wrote in message
> > > news:OlXCWS99EHA.2180@TK2MSFTNGP12.phx.gbl...
> > > > let GPIO high or low by timer interrupt to emulate time sequence of
> UART
> > > > transfer and receive, is it possible?
> > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>

Me
Tue Jan 11 10:13:34 CST 2005


"chanter" <blueenc@hotmail.com> wrote in message
news:OlXCWS99EHA.2180@TK2MSFTNGP12.phx.gbl...
> let GPIO high or low by timer interrupt to emulate time sequence of UART
> transfer and receive, is it possible?
>
>
>

Depends on the transfer speed and how accurate the timing needs to be.
And if there are any other hardware device using interrupts; other devices
may take processor time when you need it, or you may take processor time
when they need it.....