Siemens PLC intro tutorial

http://www.plc-course.com/PLC-Basics/course-of-basics-siemens-plcs.html

Siemens S7 200 System Manual

http://www.automation.siemens.com/doconweb/pdf/SINUMERIK_SIMODRIVE_04_2010_E/S7200SH.pdf?p=1

TUTORIALS

Binary Number System Basics
  http://icogsci1.ucsd.edu/~cg3x/cg3.binary.html 
ASCII Table
    http://www.neurophys.wisc.edu/www/comp/docs/ascii.html

Digital Circuits Tutorial
 http://www.hobbyprojects.com/digital_circuits.html#digital_circuits

Introduction to Digital Logic Tutorial
http://www-users.york.ac.uk/~adh2/book/ch6.htm

Ladder Logic Compared to Logic Gates
http://www.machinetoolhelp.com/Learn/ladderlogic.html

The Electronics Teacher (various quick tutorials/lessons)
http://www.electronicsteacher.com/sitemap.htm

Animated Examples of Digital Gates:
Note: go to http://www.williamson-labs.com/ click on Digital Logic
http://www.williamson-labs.com/

THE PLC TUTOR:   http://www.plcs.net/contents.shtml

OTHER TUTORIALS:  http://www.thelearningpit.com/!/tutorials.html

LABVIEW OVERVIEW AND TUTORIALS
(permission for use granted by San Diego State University)
   http://attila.sdsu.edu/me205/modules/labview.html
National Instruments Online Course for LabView
   http://cnx.org/content/col10241/latest/

PLC  AND SYSTEM SIMULATORS:
 

TRI-LOGIC: http://www.programmable-controller.com/trilogi.htm
 

RESOURCES

http://control.com

Plant Automation: 
    Link:  http://www.plantautomation.com/

Factory Automation News from Vision Systems Design

http://www.vision-systems.com/factory-automation.html

Various Automation, Tutorials Good PLC site 
    Link: http://www.thelearningpit.com

STEPPER MOTORS: TUTORIALS AND STUFF 

WITH ANAMATIONS:

  http://mechatronics.mech.northwestern.edu/design_ref/actuators/stepper_intro.html

 http://www.imagesco.com/articles/picstepper/02.html

http://www.cs.uiowa.edu/~jones/step/index.html

http://www.imagesco.com/articles/picstepper/02.html

http://www.73.com/a/0083.shtml

http://www.stepperworld.com/