Copyright (C) 1986-2009 by Daniel H. Hudgins, All Rights Reserved.

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This Web site is dedicated to the thousands of "users" of my programs, those who have helped test my programs over the last 23 or so years, and especially those who shared their experiences with me.

You must read this notice: This is a licensed Web site (HTML document and associated files). You must read and agree to be legally bound in contract by the Terms of Use and conditions given in the End User License Agreement ("EULA"), Legal Notices, Instructions, Warnings, Disclaimers, and all other text in "SECTION: 0" of "This Web Site" (HTML document and associated files) before reading or using any of the information, software programs, and or files, contained in, linked to, and or associated with, "This Web Site" (HTML document and associated files). Any use or "Beta Testing" of "This Web Site" constitutes your acknowledgment of your full agreement with the current End User License Agreement ("EULA") and your decision to have this current license supersede all prior and contemporaneous agreements and understandings. Information and files in "This Web Site" (HTML document and associated files) have been placed here so that long time users of "The Author's" programs DANCAD3D.COM (tm) , DANCAD87.EXE (tm), DANCINEL.EXE (tm), DANCINES.EXE (tm) , DANCAM.EXE (tm) , or DANPLOT.EXE (tm) could help proofread the text of the documentation files or screens displayed, and also help test data files, example files, and or any software programs that might be made available from time to time, to aid "The Author" in finding mistakes, bugs, and other errors, omissions, defects, mistakes, and faults. Everything in "This Web Site" (HTML document and associated files) is "Beta Test", "Beta Code", Experimental, Preliminary, requires proofreading, or is being evaluated for possible revision, and is NOT warranted to be free of defect. To help "The Author" report any bugs, foul-ups, defects, or mistakes that you find, see "SECTION: 8" for instructions. "This Web Site" (HTML document and associated files) and all other files and programs by Daniel H. Hudgins are made available "AS IS" without warranty of any kind express, expressed, or implied. All offers and specifications are subject to change or discontinuation without notice of any kind. Please look over "SECTION: 8" of "This Web Site" before contacting "The Author."

The pages in Section 5 mix text, photographs, and other illustrations or media in the hope that you might better understand the descriptions of how to do things that relate to testing or using the programs. Because of space limitations, the size of the graphic files associated with any down-load-able or compact distributed edition of this document might need to be small or absent. Likewise if this document is posted on the Web I might need to keep the graphic files small for two reasons, 1) the whole document will need to fit in the Web space that I can afford, 2) smaller graphic files load faster over a modem. If I someday make this document available as a CD-ROM there might be room for various sizes of each graphic file, so that you could possibly change the default size graphic files if you install the whole HTML document on your hard disk. To change the default size of the graphic, you might be able to copy the file with the same name from the sub-directory of the size you want to use to the directory with the *.htm files in it on your harddisk. The size of the graphic files will probably be indicated by the approximate horizontal number of pixels in the image before it was cropped, since I may crop some of the images to save file space. For example, files in the "320" sub-directory would be about 320 pixels wide, these might have the same filename as the files in the "160" sub-directory allowing you to copy one or the other to overwrite the same graphic filename in the default directory. The default graphic size will depend on the type of graphic file used, photographs will probably default to about 120 pixels wide, and drawings to about 800 pixels wide, but the size of files will probably be different in various distributions.

Stepper motor driver circuits operate the stepper motors by switching the power to the motor coils in a sequence that causes the motor's rotor to advance a fraction of one revolution each time a step pulse is received from the computer. The direction of the motor's rotation is controlled by the "high" or "low" logic state of the direction pin connection on the computer's parallel port. When no step pulses are received from the computer the motor's shaft remains "locked" at the last commanded position while the driver is powered.

See also the parallel port hook-up information for how to connect the stepper motor driver circuits to your computer's parallel port, such as SECTION: 5.20.1.0, or SECTION: 3.2.40.0.

Stepper motor driver circuits come in different types, principally: UniPolar, BiPolar, and MicroStep, which require that you use the corresponding, or a compatible, type of stepper motor. Which type of stepper motor driver circuit you can use with your motor depends on how many wires your stepper motor has, i.e. 3, 4, 5, 6, 8, or some other number, the way the wires connect to the coils inside the motor, and the construction of the motor.

The stepper motor driver you select to drive your motor will need to be rated to a voltage and current equal to or higher than the rating for your motor. In general stepper motors are operated at a voltage of 3 to 8 times the motor's rated voltage, so if you have a motor rated with a holding voltage of 4 volts your driver would need to be rated at 12 to 32 volts. Since stepper motors are usually rated with the current used by one coil, and two coils are normally "on" the driver might need to be rated for twice the motor's rated current depending on how the driver manufacture calculated their rating. When you operate stepper motors on voltages higher than their rated holding voltage you need to use current limiting to keep the motors within their current ratings. Current limiting is normally achieved with a series resistor, or by using a "chopper" driver circuit which turns the power to the motor on and off at high frequency to adjust the total current going through the motor's coils.

SECTION: 5.40.10.0 BIPOLAR2 stepper motor driver circuit.

SECTION: 5.40.70.0 BOOSTER circuits for stepper motors.