International Journal of Emerging Technology and Advanced Engineering Website: www.ijetae.com (ISSN 2250-2459, ISO 9001:2008 Certified Journal, Volume 5, Issue 3, March 2015) 374 Design and Implementation of a Simple HMC6352 2-Axis-MR Digital Compass C. K. Agubor 1 , G. N. Ezeh 2 , M. Olubiwe 3 , O.C. Nosiri 4 Department of Electrical and Electronic Engineering, Federal University of Technology, Owerri, Nigeria. Abstract— This paper deals with the design and implementation of a simple HMC6352 2-axis digital compass. Most compasses have been of the analogue type with magnetic needles as pointers. Replacing the “old” magnetic needle compass or the gyrocompass by an electronic solution offers advantages like having a solid-state component without moving parts and the ease of interfacing with other electronic systems. In this work, the aim is to design and implement a digital compass. To realize this, we made use of HMC6352 which is a 2-axis MR (magneto-resistive) sensor from Honeywell, Arduino Uno board with an onboard ATmega328 microcontroller chip, and a 16x2 character Liquid Crystal Display (LCD).We adopted the magneto-resistive (MR) technology as compared to flux-gate sensors common in most electronic compasses which has the disadvantage of making the device bulky. The trial test carried out with the completed HMC6352 digital compass showed a reading of 232.8 degrees West indicating its effectiveness in direction finding. Keywords—ATmega328, Compass, Earth’s magnetic field, HMC6352, Magneto-resistive, LCD. I. INTRODUCTION A compass is a navigational instrument that measures direction in a frame of reference that is stationary relative to the surface of the earth. It is a device used to determine or find geographical directions. Angle markings in degrees are usually shown on a compass. North corresponds to zero degrees, and the angles increase clockwise. East is 90 degrees, south is 180 degrees, and west is 270 degrees. These numbers allow the compass to show azimuths or bearings, which are commonly stated in this notations. The compass relies on the earth’s magnetic field to provide heading that is, angle (in degrees) and direction. It works on the principle that a suspended magnet remains in the north-south direction under the influence of the Earth’s magnetic field. Most compasses are analogue devices. This work focuses on the design and implementation of a simple digital compass. It is a low-cost, hand-held digital device. It uses HMC6352 which is a 2-axis MR (magneto- resistive) sensor from Honeywell, an Arduino Uno board with an onboard ATmega328 microcontroller chip, and a 16x2 character Liquid Crystal Display (LCD). Digital compasses find application in several areas. Its module can be integrated into a wireless consumer’s electronics such as handheld devices (e.g. cell phones, watches,etc). In a communication link set-up, the device can be used in transmitter-receiver antenna alignment. It can be used for the determination of the relative position during time intervals, where GPS signals cannot be received (e.g. when driving between high buildings). Like its analogue counterpart the digital compass can be used as a direction-finding instrument by miners in a tunnel. A. Objective of the study The main objective of this study is to design and implement a simple digital compass using the 2-axis MR sensor compass module with low power requirement and capable of providing heading accuracy in a static application environment to as low as 0.3 degrees RMS error. B. Significance of the study As navigation and orientation becomes necessary in a new information age, it is vital to have a precise and accurate digital compass. The primary function of the compass would be for navigation and orientation. This device has numerous markets it can be manufactured for. In a consumer market, it would be an indispensable aide for hikers, sailors, and for other outdoor activities where navigation is necessary. A digital compass also has viable market necessity in commercial and military applications where such applications require embedded sensors to determine a broader picture of the surrounding environment. II. LITERATURE REVIEW The 1490 sensor by Dinsmore was only designed to show direction of the horizontal pattern of the earth’s field, which made it to be a compass. This sensor provides eight directions of heading information. The 1490 sensor was internally designed to respond to directional change similar to a liquid filled compass. It will return to the indicated direction from a 90° displacement in approximately 2.5 seconds with no over-swing.