Interfacing PMDC Motor to Data Port of Personal Computer

Procedures and techniques of hardware interfacing to personal computer system through parallel data port to control permanent magnet DC (PMDC) motor and create LabVIEW integrated-development-environments (IDEs) based Virtual Instrument (VI) software are discussed. To test the designed VI software diagram, authors constructed interface hardware without taking support of any commercially available DAQ boards. Hardware resource utilization and performance optimization by creating VI are discussed. Testing the design (Hardware and VI) by varying the set point speed of the motor is concluded. It is observed that the motor speed gradually approaches and locks to the desired or set speed. 1. Introduction Computer systems are part of modern control engineering. They can be classified into many types; in general they are classified as(1)fully dedicated system,(2)partially dedicated system,(3)nondedicated system. The concept is to use the nondedicated personal computer (PC) system. PC’s use is not only limited to surfing, learning, teaching, documenting, entertainment, social gathering or communication, and so forth; beyond that, it can also be used for many other known-unknown or imagined-unimagined applications, such as interfacing and controlling the physical world parameters, without investing for expensive devices and dedicated interfacing hardware like data acquisition cards (DAQ) or signal conditioning chassis/extension boards, and so forth. Spending more money, buying the task-oriented, dedicated, costly equipment, and getting the work done are laborious. Smart move would be to get the work done by simply existing, used-unused resources with a little or no programming skills and modifications. Here, this is purely a real-time hardware implementation demonstration. The PC is used as a controller in the complete system in fact forming the open-loop control system [1–3]. 1.1. Earlier Techniques Different researchers [4–7] designed, fabricated/simulated, and studied DC motor speed controllers with different techniques and algorithms. They proposed many methods, by using PC/microcontroller with decoding circuit, and so forth. In general, if any body wants to measure and/or control the hardware with the PC and any programming language or IDE such as LabVIEW, it is essential to have DAQ Board/SCXI/PXI/PCI boards to access the data from outside world or from the PC to outside world [8]. Some of the earlier techniques are shown in Figures 1 and 2 which use below-listed devices [1, 2]:(i)PC with LabVIEW IDE,(ii)PCI plugged in DAQ board,(iii)SCXI-housing