SD4D USB with screw terminal connectors, and SD4DG with
MTA-100 connectors
The SD4D and SD4DG USB boards are designed to simultaneously operate up to four external step-and-direction driver boards (such as those produced by Applied Motion and Gecko1), allowing for easy control of up to four stepper motors. They also support "daisy-chaining" to any of our controller boards, giving you the ability to increase the number of motors which may controlled through use of one serial line.
The SD4DP USB board is a higher performance extension to the SD4D product line. Information about that board and its associated firmware is available here.
When configured with the SD4DPotRouter firmware, the SD4D and SD4DG boards permit independent control of the four motors. In addition to full serial control of each motor, the board also supports use of a user-supplied potentiometer to set target rates, combined with simple switch closures to control motor slews (thus allowing for simplified control of the motors without use of a computer). The product includes full support of separate limit switches to protect each direction of travel for each motor.
Similarly, these boards may be configured to operate in an NC (numerically controlled) process environment, through use of the SD4DNCRouter firmware option. This firmware tightly links the four motors together, providing for easy "exact straight line" and simplified arc/circle drawing. More information about the SD4DNCRouter firmware is available here.
The SD4D and SD4DG have the following key capabilities when using the SD4DPotRouter firmware:
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USB communications with a host computer may be used to control the board. |
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Alternatively, TTL-Serial communications may be used to control the board using some external microprocessor, such as a Parallax Basic Stamp TM. |
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Up to four step-and-direction stepper motor driver boards may be independently controlled at one time. |
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Limit switches may be used to automatically request motion stop of any motor in either direction. |
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Rates of 1 to 38,462 microsteps per second are normally supported. |
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Step rates are changed by linearly ramping the rates; the rate of change is independently programmed for each motor, and can be from 1 to 38,462 steps per second per second. |
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Motor coordinates are maintained as 32 bit signed values, and thus have a range of –2,147,483,647 through +2,147,483,647. |
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Both GoTo and Slew actions are fully supported. |
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Separate 'backlash' adjustments are available for each motor. |
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A TTL "busy" signal is available, which can be used to see if the motors are still moving. Note that this information is also available from the serial communications subsystem. |
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Simple control of the motors may be done by switch closure: i.e., each motor can be told to slew left or right, or to stop by simply grounding some input lines. Similarly, the rate of motion can be controlled via stepping through a standard set of rates via grounding another input. |
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Complete control of the motors, including total monitoring of current conditions, is available through the 2400 to 19,200 baud serial connection (by default, this is shipped configured for 9600 baud; other rates may be requested at the time of ordering the product). |
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An additional mode is available which allows an external computer to directly generate step sequences on the motor control lines. Up to 38,462 steps per second may be requested. |
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6 spare generic TTL I/O lines are available for input and output as needed by your application. |
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Runs off of a single user-provided 6.5 to 15 volt or 5 volt DC power supply. |
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Theoretically, an unlimited number of boards can be controlled via one serial line, if the SerRoute product is used. |
Click Here for the full PDF manual for the SD4D with the SD4DPotRouter firmware.
Click here if you need to download the current version Adobe Acrobat Reader from Adobe's site.
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All products come with a 30 day satisfaction guarantee, and the assembled products come with a 30 day return to factory warranty. Please click here for the details...
1 Note that additional external signal buffering may be needed in order for the board to operate some step-and-direction controllers, such as the Gecko products. Use of the SD4DG is recommended for such controllers.