Spinpoint M8-DVR OEM Product Manual REV 1.0
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5.2 Drive Electronics
The Spinpoint M8 hard disk drive attains its intelligence and performance through the specialized
electronic components mounted on the PCBA. The components are moun ted on one side of the PCBA.
The Preamplifier IC is the only electrical component that is not on the PCBA. It is mounted on the flexible
circuit inside the HDA. Locating the Preamplifier IC as close as possible to the read/write heads via surface
mount technology improves the signal to noise ratio.
5.2.1 Digital Signal Process and Interface Controller
The DSP core controller has a dual ARM CPU that incorporates a true 32-bit digital signal processor
(DSP),
a
bus controller unit (BCU), an interrupt controller unit (ICU), a general purpose timer (GPT), and SRAM.
5.2.2 Disk Controller
The AT disk controller works in conjunction with the DSP core to perfo rm the ATA interface control, buffer
data flow management, disk format/read/write contro l, and error correction functions of an embedded disk
drive controller. The DSP communicates with the disk controller module by readin g from and writing to its
various internal registers.
To the DSP core, the registers of the disk controller appear as unique memory or I/O loca tions that are
randomly accessed and operated upon. By re ading from and writing to the re gisters, the DSP core initiates
operations and examines the status of the different functional blocks. Once an operation is started, successful
completion or an error condition may cause the disk controller to inte rrupt the DSP core, which then e xamines
the status registers of the disk controller and determines an appropriate course of action. The local DSP core
may also poll the device to ascertain successful completion or error conditions.
Figure 5-2 illustrates the relationships between the various blocks within the AT disk controller. These
blocks will be referred to throughout this documen t.