On Fri, 26 Sep 2003 16:32:29 -0400, you wrote:

>Hi All,
>
>I'm just getting started PIC programming.  I'm pretty
>comfortable with programming but my hardware experience is
>very limited.  I'm reading as much as I can but thought
>I'd solicit some advice from the list, so here goes:
>
>My application will incorporate input from the user in the
>form of button presses or IrDA communication.  It (the
>PIC) will also be talking to a realtime clock, RAM and one
>or more serial peripherals.  It will provide output to the
>user in the form of flashes of one or more LEDs.
>
>During all of this, the program needs to remain responsive
>to both the user's button presses and to anything coming
>in from the various peripherals.
>
>I don't want my program locked up in tight delay loops
>during things like flashing an LED - if that will affect
>its responsiveness to input.
>
>How do most of you deal with issues like this?
>
>Should I incorporate a cheap 2nd PIC and use a few IO pins
>to tell it what to present to the user?  For example, 000
>=3D do nothing, 001 =3D single red flash, 010 =3D two red
>flashes, etc...  This would give me eight different output
>options and my "primary" PIC could treat it as a 'one
>shot' kind of deal - set the bits and forget about it.
>
>Am I on a decent track here - or are there better (or
>cheaper) options?

>Also - do any of you know of an IC that will do both of
>the following:  (1) Multiplex serial devices so I can use
>the PICs single UART to communicate with multiple devices,
>and (2) Buffer incoming data so I can check it at my
>liesure?
>
>Thanks for your time!

The answer to most of your questions is to use interrupts.=20
Stuff like LED flashing, buffering of input data, multiple serial ports, =
key scanning can all happen
in the background, so your main code can deal with it when it's ready, =
while time-sensitive things
are attended to promptly by the interrupt code.

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