Fujitsu MHS2020AT, Product Manual, Page: 15 / 254

Contents
C141-E171-03EN xi
4.6.1 Read/write preamplifier (HDIC) .........................................................4-10
4.6.2 Write circuit ........................................................................................4-10
4.6.3 Read circuit .........................................................................................4-12
4.6.4 Digital PLL circuit ..............................................................................4-13
4.7 Servo Control ........................................................................................4-14
4.7.1 Servo control circuit............................................................................4-14
4.7.2 Data-surface servo format ...................................................................4-17
4.7.3 Servo frame format..............................................................................4-19
4.7.4 Actuator motor control........................................................................4-20
4.7.5 Spindle motor control..........................................................................4-21
CHAPTER 5 Interface ..................................................................................... 5-1
5.1 Physical Interface ....................................................................................5-2
5.1.1 Interface signals ....................................................................................5-2
5.1.2 Signal assignment on the connector......................................................5-3
5.2 Logical Interface .....................................................................................5-6
5.2.1 I/O registers ...........................................................................................5-7
5.2.2 Command block registers......................................................................5-8
5.2.3 Control block registers ........................................................................5-13
5.3 Host Commands ....................................................................................5-14
5.3.1 Command code and parameters ..........................................................5-14
5.3.2 Command descriptions........................................................................5-18
5.3.3 Error posting......................................................................................5-104
5.4 Command Protocol..............................................................................5-106
5.4.1 PIO Data transferring commands from device to host ......................5-106
5.4.2 PIO Data transferring commands from host to device ......................5-108
5.4.3 Commands without data transfer ......................................................5-110
5.4.4 Other commands ...............................................................................5-112
5.4.5 DMA data transfer commands ..........................................................5-112
5.5 Ultra DMA Feature Set .......................................................................5-115
5.5.1 Overview ...........................................................................................5-115
5.5.2 Phases of operation ...........................................................................5-116