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stepper motor interfacing with 8085 using 8255 pdf

A stepper motor is a digital motor. It can be driven by digital signal. Fig. shows the typical 2 phase motor rated 12V /0.67 A/ph interfaced with the 8085 microprocessor system using 8255. Motor shown in the circuit has two phases, with center-tap winding. The center taps of these windings are connected to the 12V supply. Due to this, motor can be excited by grounding four terminals of the two windings. Motor can be rotated in steps by giving proper excitation sequence to these windings. The lower nibble of port A of the 8255 is used to generate excitation signals in the proper sequence. These excitation signals are buffered using driver transistors. The transistors are selected such that they can source rated current for the windings. Motor is rotated by 1.80 per excitation.

8085TRAINER KIT PS-TRAINER-8085 microprocessor trainer kit is proposed to smooth the progress of learning and developing designs of microprocessor from Intel. It has facility to connect PC’s 101/104 Keyboard, to enter user programs in Assembly languages. User verifies the programs through LCD or PC. User friendly Firmware confirms facilitating the beginners learns operations of a microprocessor quickly. STEPPER MOTOR A stepper motor is a brushless, synchronous electric motor that converts digital pulses into mechanical shaft rotation. Every revolution of the stepper motor is divided into a discrete number of steps, and the motor must be sent a separate pulse for each step.