NEC FD1165 - 2.7 Drive Identification (DX) Selection; 2.8 Option Selection

2.7 DRIVE IDENTIFICATION (DX) SELECTION
The controller identifies each disk drive in a system by the
position of the drive identification (DX) jumper on the disk
drive. When only one disk drive is used in a system, insert
the DX jumper (see Figure 2-11) to identify that disk drive
as DX1. When two to four disk drives are used in a system,
assign each one a different DX number and insert the jumper
for that unit accordingly (see Figure 2-11). A maximum of
four disk drives can be used in a system. The Model FDl165
is supplied with the DX jumper in the DXl position.
2.8 OPTION SELECTION
The Model FDl165 can be tailored to fulfill specific system
requirements by changing the positions of the option selec-
tion jumpers on the PCB. This section describes the options
that are available by using the jumpers. See Figure 2-11
for the location of the jumpers. For an explanation of the
signals that are affected by changing the option selection
jumpers, see Chapter 3.
2.8.1 Head Load Jumper (HL)
A
Head Load signal from the controller initiates head load
action when the HL jumper is in the HLl position. When the
jumper is in the HL2 position, a Drive Select signal from
the controller initiates head load action. The FDl165 is
supplied with HLl selected.
2.8.2 Radial Ready Jumper (RX)
In the RXl position, the Ready signal from the dis k dr i ve
is gated by the Drive Select signal. In the RX2 position,
the Ready signal is independent of the Drive Select signal.
The FDl165 is supplied with the RXl selected.
2.8.3 Side Select Jumper (SS)
The Side Select signal from the controller determines the
disk side when the SS jumper is in the SSl position. When
the jumper is in the SS2 position, the Direction Signal from
the controller determines the disk side. If the Direction
Signal level is High, side 0 is selected. If the Direction
Signal level i.s Low, side 1 is selected. The FDl165 is
supplied with SSl selected.
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