PC87332VLJ-5 NSC [National Semiconductor], PC87332VLJ-5 Datasheet - Page 15

• Manufacturer Part Number: PC87332VLJ-5
• Description: PC87332VLJ (3.3V/5V) and PC87332VLJ-5 (5V) (SuperI/OTM III Premium Green) Floppy Disk Controller, Dual UARTs, IEEE1284 Parallel Port, and IDE Interfac
• Manufacturer: NSC [National Semiconductor]

STB
STEP
STEP
TC
TRK0
TRK0
V
V
VLD0 1
V
V
WAIT
WR
WDATA
WDATA
WGATE
WGATE
DDB
DDC
SSB
SSD
1 0 Pin Description
Symbol
Normal
Mode
PPM
Mode
Normal
Mode
PPM
Mode
Normal
Mode
PPM
Mode
Normal
Mode
PPM
Mode
V
V
SSC
SSE
50 99
56 63
90 61
42 9
Pin
95
40
81
37
93
84
18
39
83
38
82
6
I O
I O
O
O
O
O
O
O
I
I
I
I
I
I
Data Strobe This output signal indicates to the printer that valid data is available at the printer port
This pin is in a TRl-STATE condition 10 ns after a 0 is loaded into the corresponding Control Register
bit The system should pull this pin high using a 4 7 k
Step This output signal issues pulses to the disk drive at a software programmable rate to move the
head during a seek operation
Step This pin provides an additional step signal in PPM Mode when PNF
and Table 7-5 for further information )
TerminaI Count Control signal from the DMA controller to indicate the termination of a DMA
transfer TC is accepted only when FDACK is active TC is active high in PC-AT and Model 30
modes and active low in PS 2 mode
Track 0 This input indicates to the controller that the head of the selected floppy disk drive is at
track zero
Track 0 This pin provides an additional Track 0 signal in PPM Mode when PNF
Table 7-5 for further information )
Power Supply This is the 3 3V or 5V supply voltage for the PC87332 circuitry
Valid Data These input pins are sensed during reset and indicate the state of bit 5 in the FDC Tape
Drive Register (3F3h) They indicate whether bits 6 and 7 of this register contain valid media ID
information for floppy drives 0 and 1 If VLD0 is sensed low at reset then whenever drive 0 is
accessed bit 5 of the Tape Drive Register is a 0 indicating that bits 6 and 7 contain valid media ID
information If VLD0 is sensed high at reset then whenever drive 0 is accessed bit 5 of the Tape
Drive Register is a 1 indicating that bits 6 and 7 do not contain valid media ID information The same
is true of VLD1 relative to the media ID information for drive 1
If bit 0 of FCR is 1 the VLD bits have no meaning VLD0 value during reset is loaded into bit 0 of
FCR (to select between media sense or DRATE) A 30 k
Use a 10 k
Ground This is the ground for the PC87332 circuitry
Wait This signal is used in EPP mode by the parallel port device to extend its access cycle It is
active low (See BUSY and Table 7-5 for further information )
Write Active low input signal to indicate a write from the microprocessor to the controller
Write Data This output is the write precompensated serial data that is written to the selected floppy
disk drive Precompensation is software selectable
Write Data This pin provides an additional Write Data signal in PPM Mode when PNF
and Table 7-5 for further information )
Write Gate This output signal enables the write circuitry of the selected disk drive WGATE has
been designed to prevent glitches during power up and power down This prevents writing to the disk
when power is cycled
Write Gate This pin provides an additional Write Gate signal in PPM Mode when PNF
SLCT and Table 7-5 for further information )
(Continued)
resistor to pull these pins to high during reset
15
Function
resistor (See WRlTE for further information )
internal pull-down resistor is on each pin
e
0 (See SLIN ASTRB
e
0 (See PD1 and
e
e
0 (See PE
0 (See