03-05-2012, 11:57 AM
STEPPER MOTOR CONTROL USING 89C51 MICROCONTROLLER
[attachment=21130]
Circuit description
the complete circuit of the
stepper motor controller. When power
supply switch S1 is closed, LED1 glows
to indicate the presence of power in the
circuit. Capacitor C3 connected to pin 9
(RST) provides the power-on reset to the
microcontroller.
The stepper motor
is connected to port
pins P2.4 through
P2.7 of the microcontroller
(IC2) through
the motor -dr iver
circuit consisting of
four Darlington pairs
comprising transistors
BC548 and SL100
(T1-T2, T3-T4, T5-T6
and T7-T8).
Programming
The program is written in Assembly language
and compiled using ASM51 crossassembler.
The listing file is given at the
end of this article. 89C51 microcontroller
is programmed using Atmel’s Flash programmer.
One-step rotation of the stepper motor
used in this project equals 1.8o. When you
program the motor for 200 steps, the motor
makes one complete revolution, i.e. 360o.
Construction and working
You can assemble the circuit on any general-
purpose PCB. An actual-size, singleside
PCB for the stepper motor controller is
shown in Fig. 4 and its component layout
in Fig. 5.
Mount a 40-pin IC base for the microcontroller
on the PCB, so you can remove
the chip easily when required. Normally,
six wires of different colours (two being
red) are available for connection to the
stepper motor. The sequence for connecting
the stepper motor coils to the driver
card is shown in Fig. 2.
After you are done with the hardware
part, assemble the program (stpb1.asm) using
ASM51 assembler. Load the hex file generated
by ASM51 into a programmer and burn
it into the chip. Now put the programmed
chip on the IC base on the PCB.
[attachment=21130]
Circuit description
the complete circuit of the
stepper motor controller. When power
supply switch S1 is closed, LED1 glows
to indicate the presence of power in the
circuit. Capacitor C3 connected to pin 9
(RST) provides the power-on reset to the
microcontroller.
The stepper motor
is connected to port
pins P2.4 through
P2.7 of the microcontroller
(IC2) through
the motor -dr iver
circuit consisting of
four Darlington pairs
comprising transistors
BC548 and SL100
(T1-T2, T3-T4, T5-T6
and T7-T8).
Programming
The program is written in Assembly language
and compiled using ASM51 crossassembler.
The listing file is given at the
end of this article. 89C51 microcontroller
is programmed using Atmel’s Flash programmer.
One-step rotation of the stepper motor
used in this project equals 1.8o. When you
program the motor for 200 steps, the motor
makes one complete revolution, i.e. 360o.
Construction and working
You can assemble the circuit on any general-
purpose PCB. An actual-size, singleside
PCB for the stepper motor controller is
shown in Fig. 4 and its component layout
in Fig. 5.
Mount a 40-pin IC base for the microcontroller
on the PCB, so you can remove
the chip easily when required. Normally,
six wires of different colours (two being
red) are available for connection to the
stepper motor. The sequence for connecting
the stepper motor coils to the driver
card is shown in Fig. 2.
After you are done with the hardware
part, assemble the program (stpb1.asm) using
ASM51 assembler. Load the hex file generated
by ASM51 into a programmer and burn
it into the chip. Now put the programmed
chip on the IC base on the PCB.