Functional Description

Operating Modes

 

 

2.3OPERATING MODES

The Zeus SSD is configured as a high-performance I/O device, supporting the following operating modes:

•Primary drive address at system ATA I/O address 1F0h - 1F7h and 3F6h - 3F7h. The host must provide chip-enable #CS0 and #CS1. The SSD decodes addresses DA0 - DA2.

•Secondary drive address at system ATA I/O address 170h - 177h and 376h - 377h. The host must provide chip-enable #CS0 and #CS1. The SSD decodes addresses DA0 - DA2.

2.3.1I/O Primary and Secondary ATA (IDE) Modes

Primary and secondary drive addressing modes allow hosts to use the ATA-standard’s reserved disk drive I/O addresses. This provides computer system designers with the simplest way to accommodate ATA-protocol devices.

2.3.1.1Addressing Modes

Zeus SSDs, on a command by command basis, can operate in either CHS or LBA addressing modes. Identify Drive Information (see “Identify Drive Information” on page 23) tells the host whether the drive supports LBA mode. The host selects LBA mode via the Drive/Head register. Sector Number, Cylinder Low, Cylinder High, and Drive/Head register bits HS3=0 contain the zero-based LBA. The drive's sectors are linearly mapped with: LBA = 0 => Cylinder 0, head 0, sector 1. Regardless of the translation mode, a sector LBA address does not change. LBA = (Cylinder * no of heads + Head) * (sectors/track) + (Sector - 1). Table 6 on page 21 lists the supported IDE addressing modes.

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Zeus Ultra DMA Solid State Drives