Roman Dremov wrote:

> Hi all,
> First, let me thank everybody who replied on my request.
> Probably, I should be more concrete.
> I know the basics of D/A conversion, but I am absolute
> novice in MCU designed devices.
>

if you need this in a lab or someplace where size is not a consideration, maybe
just use a pc's parallel port to control an A/D, it would be much simpeler,
since you dont have the experience with pics or the programming tools. Make a
DOS program to send the data to the D/A

> I need the linear voltage source to control the high power
> current source (120 A) which drives the superconducting magnet (9 T).
> Well, the old source has 10 bit resolution, and the field steps are
> not suitable for me. I think, 16 bit will be ok and let me fine tuning.
> About the scales:
>  voltage output - -5...0...+5V (and this is ok with MAX542 + MAX495)
>  one step duration - >5 msec. (the whole range - not faster then 500 sec)
> I just don't know will , for instance, pic16c84 be enough for my purpose?
> I need to be able to change both Vend and Tstep from some small keyboard
> (and also computer), see the settled values on the LED/LCD 6 digit display,
> have some protection (low limit for Tstep, upper - for Vend),
> START/STOP control.
> I have an idea how to make all of these by means of logic IC's, but may it
> be more powerful and simple to use some cheap PIC MCU ?
> If somebody has any ideas (experience) in that?
> Useful links can also help me.
>
> --
> ---------------------------------------------------------
> |   Roman Dremov                      Na Slovance 2     |
> |   Institute of Physics              180 40 Prague 8   |
> |   Academy of Sciences               Czech Republic    |
> |      phone:  +4202-21912736    fax: +4202-21912567    |
> |       home:  +4202-8551040     (extension 794)        |
> |     e-mail:   dremov@fzu.cz    ICQ: 13114621          |
> |        WWW:   http://www.fzu.cz/~dremov               |
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