This device is an alternative for complicated stepper motors drivers, which needed LPT port and complicated software.
It is a simple driver of two unipolar motors, that allows to perform a set number of steps to the left or the right. Speed is rigidly defined in the microprocessor program. Engine control is via the terminal according to the scheme m0l2000, where m0 is the engine number (or m1), l is left (or r), 2000 – number of steps.
The scheme of the driver:
Leg 16 max232 should be connected to +5V, leg 15 to the mass, and a capacitor 100nF should be soldered between them. Additionally, capacitors c1-c4 should be changed to 1uF. Another matter is the system based on AT90S2313, which is not produced any more. It can be replaced with Attiny2313. For this reason, an internal resonator <8MHz should be set in the fusebits and dividing by 8 off (bitC). The charge does not need changes.
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Prosty sterownik PC silnika krokowego