Read/Write Asic - Quantum FIREBALL PLUS AS 10.2 Product Manual

5.2.1.5 5.2.1.5 5.2.1.5 5.2.1.5 Buffer Controller Buffer Controller Buffer Controller Buffer Controller
The Buffer Controller supports a 2 MB buffer, which is organized as 1M x 16 bits.
The 16-bit width implementation provides a 60 MB/s maximum buffer bandwidth.
This increased bandwidth allows the µProcessor to have direct access to the buffer,
eliminating the need for a separate µProcessor RAM IC.
The Buffer Controller supports both drive and host address rollover and reloading,
to allow for buffer segmentation. Drive and host addresses may be separately loaded
for automated read/write functions.
The Buffer Controller operates under the direction of the µProcessor.
5.2.1.6 5.2.1.6 Servo Processor Servo Processor
5.2.1.6 5.2.1.6 Servo Processor Servo Processor
The Servo Processor in the Read Write Channel ASIC provides servo data recovery
and burst demodulation to extract the actuator position information. This
information is processed in the controller ASIC/microprocessor, and a control
signal is output to the VCM in the Power ASIC. This controls the current in the
actuator coil which controls the position of the actuator.
5.2.1.7 5.2.1.7 Read/Write Interface Read/Write Interface
5.2.1.7 5.2.1.7 Read/Write Interface Read/Write Interface
The Read/Write interface allows the integrated µprocessor, disk controller to
communicate with the Read/Write chip.
5.2.1.8 5.2.1.8 ATA Interface Controller ATA Interface Controller
5.2.1.8 5.2.1.8 ATA Interface Controller ATA Interface Controller
The ATA Interface Controller portion of the ASIC provides data handling, bus
control, and transfer management services for the ATA interface. Configuration
and control of the interface is accomplished by the µController across the MAD
bus. Data transfer operations are controlled by the Buffer Controller module.
5.2.1.9 5.2.1.9 Motor Controller Motor Controller
5.2.1.9 5.2.1.9 Motor Controller Motor Controller
The Motor Controller controls the spindle and voice coil motor (VCM) mechanism
on the drive.
5.2.2 5.2.2

Read/Write ASIC

Read/Write ASIC
5.2.2 5.2.2 Read/Write ASIC Read/Write ASIC
The Read/Write ASIC integrates an Advanced Partial Response Maximum
Likelihood (PRML) processor, a selectable code rate Encoder-Decoder (ENDEC),
and a Servo Processor with data rates up to 340 MHz. Programming is done
through a fast 40 MHz serial interface. The controller and data interface through an
8-bit wide data interface. The Read/Write ASIC is a low power 3.3 Volts, single
supply, with selective power down capabilities.
The Read/Write ASIC comprises 12 main functional modules (described below):
• Pre-Compensator
• Variable Gain Amplifier (VGA)
• Butterworth Filter
• FIR Filter
• Flash A/D Converter
• Viterbi Detector
• ENDEC
• Servo Processor
Quantum Fireball Plus AS 10.2/20.5/30.0/40.0/60.0 GB AT
Basic Principles of Operation
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