SMO-F551 Technical Guide and Specifications
37
Sony Corporation 1998
DSP/Servo Blocks
The SMO-F551 contains the following four servo blocks:
Spindle Servo
The spindle servo block rotates the disk at 3,000 min
-1
(rpm) or 3,600 min
-1
(rpm)
using a phase-locked-loop servo system which uses the Frequency Generator (FG)
signal.
Focus Servo
The focus servo block controls the two axis actuator to focus the laser diode beam on
the disk's surface by the beam-spot-size method.
Tracking Servo
The tracking servo block controls the two axis actuator to follow the track using the
Push-Pull servo system.
Slide Servo
The slide servo block drives the slide motor(flat linear motor) for accessing to the
designated track(s).
These servos are controlled by the Digital Signal Processor (DSP) block, consisting of
12 kwords RAM. This block controls the analog and mechanical blocks.
Integrated Optical Controller Block
The integrated optical controller includes the following blocks:
Buffer Memory Manager
This module performs the internal data bus management and generates address for
Buffer Memory. The data to/from the Buffer Memory is transferred in the DMA mode.
The Buffer Memory Manager arbitrates DMA requests according to the priority of each
channel.
SCSI Controller
The SCSI controller controls the SCSI bus and transfers data to/from the internal bus.
This SCSI implementation conforms to SCSI specification, ANSI X3.131-1994. User
data to/from the Buffer Memory are transferred in the DMA mode.