clock driver for sparkfun easydriver breakout

Posted on Feb 5, 2014

This is a project I`ve done on behalf of a person on an internet forum. The requested operation is simple: Use an EasyDriver stepper motor driver and a 1. 8 deg/rotation stepper motor and make the motor turn one revolution per minute. This frees me up a bit not having to select and source products myself, nor having to implement the actual stepper

clock driver for sparkfun easydriver breakout
Click here to download the full size of the above Circuit.

driver myself. The EasyDriver is REALLY simple in operation. Connect 7-30v DC to M+ (and ground to GND), connect a stepper motor to A and B and the motor automatically steps once for each LOW->HIGH transition on STEP. The direction is dependent on the state of DIR (+5v or ground). MS1 and MS2 together defines the step resolution. The driver chip is a Allegro A3967SLB, so the truth table for MS pins can be found in it`s datasheet, page 2. The breakout board has pull-up resistors on both MS1 and MS2, which puts it in eight-step resolution as standard. To alter MS1 and MS2 you simply pull them to ground individually based on your desired resolution. I decided to make a few improvements to the requested operation. Via a DIP-switch the user can select the resolution for the EasyDriver while simultaneously altering the steps/minute so it will always make one turn per minute even though the step resolution is changed. There is also an LED to indicate each step. I used a four-way DIP switch, the two remaining switches I used for step direction and to simply turn the steps on or off. The DIR signal is pulled up to +5v by a 10k resistor My circuit is built on a strip board and is based on an AtTiny25. It`s system clock is driven by a low frequency 32. 768kHz watch crystal. It`s important to program the correct fuse bits for low frequency crystal oscillators! On to the code. I`m using Timer 0 with system clock as clock source in...

Leave Comment

characters left:

New Circuits



Popular Circuits

Transistor Checker with 555
Automatic Gain Control ( AGC )
Precision voltage-to-frequency converter
Attendance counter
Speech with XR-T5995
ATmega16 Programmer
pic 16f887 based digital thermometer
High Quality Intercoms
Active Filter Design with OpAmps
Cortex M3 MCU features USB firmware protection
Infinity Bug