Emulex MD21/S2, Техническое руководство

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Disk Drive Interface
7.3.1.2 Input Signal Characteristics
When measured at the ESDI device's connection, each signal received
by an ESDI device has the following input characteristics:
• Signal true = 0.0 VDC to 0.5 VDC
• Signal false = 1.4 VDC minimum
7.3.1.3 Termination
All assigned signals are terminated with 220 ohms to +5 VDC and 330
ohms to ground at each end of the cable.
7.3.3..4 ESDI Signals
The pin/signal assignments for control signal interface between the
MD21 Controller and an ESDI disk drive are shown in Figure 7-4 and
Table 7-4.
The pin/signal assignments for data signal interface between the
MD21 Controller and an ESDI disk drive are shown in Figure 7-5 and
Table 7-5. As indicated in the figure, lines 2, 5, 9, and 20 are
connected to ground at the MD21 data interface. The MD21 does not
use lines 2 and 20 to report the sector and index positions from
each drive (as indicated in the ESDI specification), but uses the
sector and index lines on the control cable for the selected drive.
7-14 Interfaces