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SMSC DS – FDC37N958FR
Page 4
Rev. 09/01/99
DESCRIPTION OF PIN FUNCTIONS
PinPin
PIN #
NAME
DESCRIPTION
SUPPLY
VOLTAGE
TYPE
183
nFWR
Flash Memory Write
VCC1
O8
181
FALE
Flash Address latch Enable
VCC1
O8
KEYBOARD
36:30,
28:22
KSO[0:13]
Keyboard Scan Outputs(14*8 = 112)
Configuring GPIO4 and GPIO5 as
KSO14 and KSO15 yields a scan
matrix of 16 x 8 = 128.
VCC1
OD4
44:37
KSI[0:7]
Keyboard Scan Inputs
VCC1
ISP
193
nEA
External Access for 2K ROM
VCC1
I
45
EMCLK
EM Serial Clock
VCC2
I/OD 24
46
EMDAT
EM Serial Data
VCC2
I/OD 24
47
IMCLK
IM Serial Clk
VCC2
I/OD 24
48
IMDAT
IM Serial Data
VCC2
I/OD 24
50
KBCLK
KBD Serial Clock
VCC2
I/OD 24
51
KBDAT
KBD Serial Data
VCC2
I/OD 24
52
PS2CLK/
8051RX/
GPIO[20]
PS2 Serial Clock
VCC2
I/OD24
53
PS2DAT/
8051TX/
GPIO[21]
PS2 Serial Data
VCC2
I/OD24
SERIAL IRQ / UART IRQS
101
SIRQ /
IRQ3(UA1)
Serial Interrupt
UART1 Interrupt
VCC2
I/O24
/O24
99
PSBCLK
PCI Clock input
VCC2
I
100
PSBDAT
UART2 Interrupt
VCC2
I/O24
/O24
FDD INTERFACE
The following FDC output pins can be configured as either Open Drain outputs capable of
sinking 24mA (OD24) or as push-pull outputs capable of driving 12mA and sinking 24mA (O24).
The FDC output pins must tristate when the FDC is in powerdown mode (The board designer
must provide external pull-up resistors on these output pins).
17
nRDATA
Read Disk Data
VCC2
IS
12
nWGATE
Write Gate
VCC2
O24/
OD24
11
nWDATA
Write Disk Data
VCC2
O24/
OD24