A DSP BASED HARD-DISK DRIVE SERVO TEST STAND

The paper reports the development of a hard disk drive (HDD) servo tes t stand developed to demonstrate the principles of a hard disk drive s ervo system for teaching and research, The test stand consists of a se rvo written head disk assembly, electronic circuits to process the HDD signal to obtain position information, a 16-bit digital signal proces sor (DSP) and a spindle motor controller, Hard disk drive servo contro l related internal signals such as the read signal, peak detector outp ut, servo gate and servo bursts are made available for probing, A host PC is used for down loading commands and controller parameters to the DSP and up-loading the results of the servo system for display and po st-processing. Implementation results of a PTOS servo controller and s ystem identification are presented.