Re: using 8051ports

You mean the very same ports that are used for the external
memory ? Well as long as you can guaranteed that during a
port access no external memory byte is changed plus that
during a memory access the port hardware is not reacting
either. I'd not do it as it becomes a source of programming
errors especially when using a compiler.

Rene

Aliasger wrote:
> Thanks for the response. 
>
> But I also wanted toknwo about the ports. Can they be used while
> accessing the external memory? I read somewhere that they can and
> somewhere else that they can't be used for dual purpose.
>
> Waiting for the reply.
>
> Ali
>
> Rene Tschaggelar <[EMAIL PROTECTED]> wrote in message news:<[EMAIL PROTECTED]>...
>
> > Aliasger wrote:
> >
> > > Hi,
> > >
> > > Just wanted to know if there is any way to use port P0 and P2 while
> > > accessing external memory, or do you have to go in for 8255s?
> > >
> > > I want to develop an application which has a really low number of
> > > components on the PCB.
> >
> > You can achieve a low component count by implementing some
> > peripheral devices into a CPLD or FPGA.
> >
> > Rene