Help with PIC selection

From: James Lerch (jlerch_at_no.spam.tampabay.rr.com)
Date: 02/20/05 

Date: Sun, 20 Feb 2005 17:39:36 GMT

Greeting All,

I've been looking for an excuse to play with PICs and I think I've
finally found one. The question is, which PIC do I want to start
playing with?

The goal:

Control 6 bipolar stepper motors with a hand pad. The 6 steppers will
be configured in two sets of 3. Each set of 3 steppers will control
the tip / tilt / piston action of a telescope primary mirror.

Here's a picture to show what I mean:
http://lerch.no-ip.com/atm/Stepper_Idea.jpg

In the picture an arrow points to the three manual knobs I use to
perform the action. I'd like to replace the knobs with stepper
motors, so I can do the adjustments while I view thru the system.
BTW, the picture shows one primary for a Bino-Scope, thus the need for
6 stepper motors.

Requirements:

#1 At least 24 digital outputs

#2 A single analog input (stepper motor speed)

#3 6 digital inputs for hand pad buttons

Loose Preferences:

#1 Programmable in Basic, else Assemble, else some version of C (in
order of how comfortable I am with each language)

#2 I don't think I need a high speed PIC, nor do I think I need much
for memory. (but what do I know)

#3 Something cheap and easy would be nice.

Of course, I don't have any PIC experience yet, so I'd be starting
from the ground up. However, I do have a lot of experience
controlling stepper motors from a personal computer, so at least I
have some clue as to what I need to do..

Any suggestions would be greatly appreciated.

 
Take Care,
James Lerch
http://lerch.no-ip.com/atm (My telescope construction, Testing, and Coating site)

Press on: nothing in the world can take the place of perseverance.
Talent will not; nothing is more common than unsuccessful men with talent.
Genius will not; unrewarded genius is almost a proverb.
Education will not; the world is full of educated derelicts.
Persistence and determination alone are omnipotent.
Calvin Coolidge

Relevant Pages

  • Re: DIY CNC Machine How Hard Can It Be?
    ... With stepper control, at least, my experience has been that there is a ... And if you want the stepper to be able to go at more than a tiny fraction of ... stepper motors cannot stop suddenly without first ramping ... sometimes cutting through the first tracks. ...
    (sci.electronics.design)
  • Re: Stepper motor from Princess Auto?
    ... Hi Rod, ... This website is not new, but if you wish to read about stepper motors ... and their control by computers, I have yet to see anything better. ...
    (alt.machines.cnc)
  • Re: Stepper motor PID control
    ... Most stepper motors use a closed loop system otherwise the ... possible to control a stepper motor in a closed loop system via a ... it will limits axis overshoot and precise positioning without ...
    (comp.arch.embedded)
  • Re: Help with PIC selection
    ... >In the picture an arrow points to the three manual knobs I use to ... >#1 Programmable in Basic, else Assemble, else some version of C (in ... >Of course, I don't have any PIC experience yet, so I'd be starting ... >controlling stepper motors from a personal computer, ...
    (sci.electronics.design)