At 15.16 1995-11-07 +0100, Roman VALEHRACH wrote:

>Hi to all PICers out there!

Oh my, what a letter, almost as long as a spam ;)

-- chop --- chop --

>* What is the best way to do multiple tasks with a PIC (esp. 16C84)?

Use a "state" variable to control where you are in each task and execute
each task in turn via some time sharing scheme, e.g. 2ms for you, 5ms for
you and so on. To control time, you can setup a timer to count down to zero
and then generate an interrupt - set a flag and the current task will finish
what it's doing when the task checks this flag. Each critical input (such as
waveform period measurements) could generate interrupts on selected edges
and store these measurements for further processing in the appropriate task(s).

Just some thoughts ... hope it gives you some new ideas ...

>* Which (power) transistors should I use in the final stage?

I say, read the specifications and look at some examples in the data sheets.
Then try it out on a protoboard (maybe not 20A though).

To measure Rds[on] you can setup a test circuit with high power resistors
and try it out in practise. I did so when I started to build a mega led
display with over 1000 leds and controlled by the well-known Z80-processor.
(The project is currently on halt, I wonder why?)

-- chop --- chop --

>C. Experience:
>   I'm still very new to the PICs. I know it will be a hard way to a functinal
>   unit but I certainly will learn my share.

A small advice ... start with a simple project to learn the basics. I
started with the '54 and I was surprised how much code you actually could
fill it with.


-- Conny