Building a serial remote

[Darren]

I'm trying to build a remote control that works over serial.

I've never tried anything like this before so I don't know how to go about
it.

I know I need a 232 driver chip to convert the voltage from a 5v PIC output
to the 12v serial link.

What I really need is a circuit diagram and advice on which PIC to use to
create a serial bit stream and if possible some code to do it.

It needs to have about 13 buttons on it, and if possible a small (6 or 8 by
1) backlit LCD to receive text, the backlight should turn off after about
10 seconds, and there should be a switch to turn the remote off completely
to stop accidental button pressses.

There seems to be so many programmable chips that have all sorts of options
but I don't know which is best.

Thanks
Darren

 

[Anthony Fremont]

I'm trying to build a remote control that works over serial.

I've never tried anything like this before so I don't know how to go about
it.

I know I need a 232 driver chip to convert the voltage from a 5v PIC output
to the 12v serial link.

What I really need is a circuit diagram and advice on which PIC to use to
create a serial bit stream and if possible some code to do it.

It needs to have about 13 buttons on it, and if possible a small (6 or 8 by
1) backlit LCD to receive text, the backlight should turn off after about
10 seconds, and there should be a switch to turn the remote off completely
to stop accidental button pressses.

There seems to be so many programmable chips that have all sorts of options
but I don't know which is best.

If you're going to use a PIC, then look at the 16F628 or 16F88. These
are the "generic" 18pin parts, the 88 contains real ADC's whereas the
628 contains only comparators. The 16F876 and 16F877 are nice 28 and 40
pin parts respectively.

If you are just starting out with PICs, you may wish to learn the
18F452. It is a 16bit instruction word core with many enhancements over
the 16F series.