The BS0710-USB board is a complete Unipolar/Bipolar dual stepper motor controller system which can be controlled from a microcontroller using the serial interface or a PC using the USB connection. It includes the capability of driving one or two stepper motors, each of which being either unipolar (4-pole) or bipolar (2 pole). This unit is a good choice for those designing products using linear actuators, especially since the micro stepping features will reduce noise levels and can increase positional accuracy by a large amount.

The board is specified as allowing up to 1 amp per winding, with 6.5 to 15 volt motors supported when in single power supply mode. It also supports a dual power supply feature, wherein the motors use a separate supply from the logic circuits; in this mode, up to a 34 volt power supply may be used for the motors.

Features:

• Up to two Unipolar 4-pole stepper motors may be independently controlled at one time.
• Each motor may draw up to 1 amp per winding.
• Limit switches may be used to automatically request motion stop of either motor in either direction.
• Rates of 1 to 62,500 microsteps per second are supported.
• 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 62,500 microsteps per second per second.
• All motor coordinates and rates are expressed in programmable microstep units of 1/2 to 1/64 of a full step.  Once the base step size is selected, changing stepping modes between half, full and micro does not change any other value other than which winding pairs may be driven at the same time.
• Motor coordinates are maintained as 32 bit signed values, and thus have a range of –2,147,483,647 through +2,147,483,647.
• Both GoTo and Slew actions are fully supported.
• Four modes of stepping the motor are supported: Half steps (alternates 1 winding and two windings enabled at a time), Full power full steps (2 windings enabled at a time), Half power full steps (1 winding enabled at a time), Near-constant-current microsteps (each from 1/64 to 1/2 of a full step)*.
• 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.
• Complete control of the motors, including total monitoring of current conditions, is available through the USB serial connection.
• An additional mode is available which allows an external computer to directly generate step sequences on the motor control lines. Up to 62,500 microsteps per second may be requested.
• Runs off of a single user-provided 6.5 to 15 volt regulated DC power supply.   May also be configured using a split supply, wherein the motor runs off of a 5 to 26 volt DC power supply, while the logic circuit runs off of a 6.5 to 15 volt DC supply.
• Connector options exist to allow use of MTA-100 locking SIP header connectors or terminal block (screw terminal) connectors for most external connections.
• Theoretically, an unlimited number of boards can be controlled via one serial line, if the SerRoute firmware is used on some of our boards to route to serial data.

Key Specifications:

• Power requirements: 6.5V - 15V @ 300 mA (Logic only)
• Communication: Asynchronous Serial @ 2400/9600 bps via TTL Serial or USB interface.
• Dimensions: 3" x 2-1/4" x 0.5" (75 mm x 56 mm x 15 mm)
• Operating temp range: 32°F to 122°F (0°C to 50°C)

*The SS0710USB uses the same firmware as the BiStep series of products; however, the base board was designed with half-stepping unipolar control in mind. For operation to 1/16th of a full step, the SimStep and BiStep product capabilities are equivalent;  however, for resolutions finer than 1/16th of a full step, the BiStep series of offerings provide better positional precision.

Downloads:
Parallax Quick Start Guide (.pdf)