Seagate Spinpoint M8, Руководство по эксплуатации продукта

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Spinpoint M8 Product Manual REV 2.6
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5.2 D r i v e Electronics
The Spinpoint M8 hard disk drive attains its intelligence and performance through the specialized
electronic components mounted on the PCBA. The components are mounted 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 perform the ATA interface control, buffer
data flow management, disk format/read/write control, and error correction functions of an embedded disk
drive controller. The DSP communicates with the disk controller module by reading 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 locations that are
randomly accessed and operated upon. By reading from and writing to the registers, 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 interrupt the DSP core, which then examines
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 document.