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This is a multi purpose motor controller that can control: * 4 DC motors single direction on/off OR * 2 DC motors forward/reverse on/off OR The controller is very easy to use because it uses a TEXT serial interface that can be connected to a PC via the RS232 COM port or to a microcontroller UART. See the description on the serial interface below. The full datasheet for this can be found at www.pin1.org . The BV4113 is a small PCB approximately 39mm x 32mm (1-1/2" x 1-1/4"). It has a microcontroller that handles the serial interface and and the 'intelligence' required to control the stepping action of the stepper motors and control the DC motors. The driver for the motor/s is an L293D chip that has internal diode protection and is capable of supplying up to 600mA with 1.2A peak. The chip can be powered separately with up to 36V from the PWR pins shown in the picture top left. In addition to controlling motors there are 2 general purpose input / output lines and a 10 bit analogue input, these can be used for sensing devices and are all operated through the serial interface. The analogue input can be read as an absolute value or as a percentage and the reference is taken form the +5V supply. Up to 4 DC motors can be connected and driven in one direction only but it is more likely that 2 motors will be connected which enables full control: The motors can be driven forward, reverse, stop and start. The serial commands are simplified in that MA1 will drive motor A in one direction and MA2 will drive the motor in the other direction whilst MA0 will stop the motor. The speed of the motors can be controlled with a pulse width modulator that is built into channels A and B. This modulates the enable lines of the L293 chip. When channel A is deactivated, this also deactivates the L293 chip, thus only the microcontroller is running reducing power consumption considerably. This feature can be disabled by removing the PWR jumper, this is in fact a thin PCB track that can be cut. The BV4113 can control bi-polar (4 wire) and unipolar (5 & 6 wire) stepper motors, there are options for continuous stepping in either direction and also a fixed number of steps (up to 65534) can be selected. The number of steps to go can also be monitored through the serial interface. To give flexibility the step speed, ramp up and step pattern can also be controlled. In addition to this the step mode: Half step or Full step can be selected. The serial interface consists of 5 connections, of which, only four will be used at any one time. The connection details are as follows: There are two interface options, RS232 via a standard PC COM port (Pins 4 and 2) or from a microcontroller UART (pins 1 and 2). As an example to interface to a standard 9 pin D type connector the following connections would be made. Only three wires are required from the COM port to the BV4113. There is no hardware handshaking so the pins in the above table should be connected together as indicated (1,6,4: 9 and 8). Connection to a microcontroller would be similar except that pin 1 would be used instead of pin 4. ** An RS232 connector is available at or contact the seller for an all in price The interface is fully configurable by software commands. From the factory the software will detect the Baud rate automatically, this is achieved by pressing CR All commands are in ASCII text, some examples: change the default step pattern Change the step mode to half step Set speed of motor connected to channel A to 50 (this is relative) There are over 30 commands to control and configure the motor control and serial interface. * Easy to use asynchronous serial interface requiring only 4 connections. * Only 2 data lines required, transmit and receive. The device will work with transmit only. * Many devices can use the same two data lines * Each device has it’s own user configurable address * No specialist hardware, can work from a PC Com port * Automatic Baud rate detection up to 38.4K, non-standard baud rates can be detected making interfacing with microcontrollers easier * Simple software requirement for interfacing with a microcontroller. * Common protocol used throughout range, devices can be mixed on same data bus * Works with RS232 standard voltages and +5V, no level translator needed for receiving data * Drive current 600mA, up to 36V (total power 4W) * Up to 4 DC motors or one stepper motor either bi-polar or uni-polar * PWM control for each DC motor when used in differential mode (forward and reverse) * Differential mode, forward and reverse * Half step or full step patterns, user definable full step pattern * Continuous stepping or pre-defined number of steps * Step read capability to indicate number of steps to go. * Step speed controllable from 128us delay between steps to 32ms in 256 increments. * Ramp up available for slow start. * Two general purpose digital input / output lines * One 10 bit analogue input channel Voltage range 4.5 to 6.5 (works on 6V battery if required) - serial interface Current consumption 2mA aprox, power down mode (We do not proofread any ads submitted by members) |
N_Carpenter@desmoines-classifieds.com (Neil Carpenter) for more information. Your emails will be instantly forwarded to the poster's private address.
