I have been experimenting with controlling a stepper motor using the EB-011 Power Board.
This is a simple example of how to program a variable step / direction system.
Hardware Connections
EB-006 Multi-Programmer with PIC 16F877A
Port A = Custom 4 x 20 LCD Display
Port B = EB-007 Switch Board
Port C = EB-011 Power Board
Port C= EB-004 LED Board
Port D = EB-014 Keypad
Astrosyn Y129-5 Unipolar Stepper Motor (Rapid Electronics)
Bit 0 = A1 = Brown
Bit 1 = A2 = Red
Bit 2 = B1 = Orange
Bit 3 = B2 = Yellow
Center Taps = Ground = Black & White
Motor Details
Full Step Mode
1.8° / Step = 200 Steps / Revolution
Half Step Mode
0.9° / Step = 400 Steps / Revolution
Program Details
The LED board in series with the power board shows the status of the 4 lines driving the stepper motor.
A simple title screen is shown, with a slight delay to allow it to be read.
The title screen then clears.
The program first requests the direction the motor is needed to turn in.
Press Sw0 = Forward
Press Sw1 = Reverse
Then the number of steps needed is entered on the keypad.
If the number is less than 100, the # key is pressed to end the enter cycle.
The motor will then turn the required number of steps, showing the number on the display.
The display will then clear and ask for the direction for the next movement.
To change between full or half step the stepper component must be edited and the program recompiled to the device.
- Stepper Driver.JPG (127.85 KiB) Viewed 5896 times
This allows the entry in degrees. Motor will turn through the value entered.
It does have a slight bug, in the accuracy as I've not used floating point math to calculate the steps from degrees
This is done by
Steps = ( Degrees / 1.8 )
Ive used
Steps = ( Degrees * 9 ) / 5
I will test it later. At the moment I am a little busy. Nice you share your projects.