HP Compaq dc7700 CMT, Техническое справочное руководство

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5-6 www.hp.com Technical Reference Guide
Input/Output Interfaces
Diskette Drive Interface Control
The BIOS function INT 13 provides basic control of the diskette drive interface. The diskette
drive interface can be controlled by software through the SCH5317's I/O-mapped registers listed
in Table 5-5. The diskette drive controller of the SCH5317 operates in the PC/AT mode in these
systems.
Table 5-5.
Diskette Drive Interface Control Registers
Primary
Address
Second.
Address Register R/W
3F0h 370h Status Register A:
<7> Interrupt pending
<6> Reserved (always 1)
<5> STEP pin status (active high)
<4> TRK 0 status (active high)
<3> HDSEL status (0 = side 0, 1 = side 1)
<2> INDEX status (active high)
<1> WR PRTK status (0 = disk is write protected)
<0> Direction (0 = outward, 1 = inward) R
3F1h 371h Status Register B:
<7,6> Reserved (always 1’s)
<5> DOR bit 0 status
<4> Write data toggle
<3> Read data toggle
<2> WGATE status (active high)
<1,0> MTR 2, 1 ON- status (active high) R
3F2h 372h Digital Output Register (DOR):
<7,6> Reserved
<5,4> Motor 1, 0 enable (active high)
<3> DMA enable (active high)
<2> Reset (active low)
<1,0> Drive select (00 = Drive 1, 01 = Drive 2, 10 = Reserved, 11 =
Tape drive)
R/W
3F3h 373h Tape Drive Register (available for compatibility) R/W