Markus asked:

    No problem there. Does anyone have code and hardware descriptions
    (board layout ? he asks hopefully) for a r/c electronic speed control
    based on a PIC ?

Well in the July '95 issue of Circuit Cellar Ink there is an article
(by me) on building an electronic speed control out of a 16C54. The
specs are:

        single input, bidirectional control (.8ms = full reverse, 2.1ms =
        full forward with 100 proportional steps in between. 1.4 - 1.6
        mS == brake (lower legs of the bridge shorted))

        output is four bits (high side left and right, low side left and right)
        that I use to drive an optoisolator and from there a MOSFET bridge.

The output is a 2Khz PWM waveform. (You can get 4Khz if you only want
50 forward and reverse directions)

I didn't think of adding soft-start, that might be possible (the PIC
is _really_ busy capturing the input pulse and converting it to PWM)

I've got the code in both MicroChip and Parallax mnemonics, I'll check
with CCI about releasing it prior to publication.

As for a stepper controller that would be pretty cool to but I've not
done that one.

My speed control uses port a (0 - 3) to control the bridge and one bit
of port B for input. Someone (I'm terrible with names, sorry about that)
suggested that if they would like it to simply take an 8 bit value (signed)
for speed. That could easily be done as well (actually it would free up
some cycles for other stuff like braking.)

--Chuck