DESCRIPTION OF PIN FUNCTIONS
BUFFER
QFP/
TQFP
PIN NO.
TYPE
NAME
SYMBOL
DESCRIPTION
60
Paper End
PE
I
Another status output from the printer, a high
indicating that the printer is out of paper. Bit 5
of the Printer Status Register reads the PE
input. Refer to Parallel Port description for
use of this pin in ECP and EPP mode.
59
75
Printer Selected
Status
SLCT
nERROR
I
I
This high active output from the printer
indicates that it has power on. Bit 4 of the
Printer Status Register reads the SLCT input.
Refer to Parallel Port description for use of this
pin in ECP and EPP mode.
nError
A low on this input from the printer indicates
that there is a error condition at the printer. Bit
3 of the Printer Status register reads the
nERR input. Refer to Parallel Port description
for use of this pin in ECP and EPP mode.
63-66
68-71
Port Data
PD0-PD7
IOCHRDY
I/O24
The bi-directional parallel data bus is used to
transfer information between CPU and
peripherals.
100
IOCHRDY
OD24P In EPP mode, this pin is pulled low to extend
the read/write command. This pin has an
internal pull-up.
IDE/ALT IR PINS
24
nIDE Enable
nIDEEN
O24P
This active low signal is active when the IDE is
(Note 1) enabled and the I/O address is accessing an
IDE register.
Interrupt Request IRQ_H
H
024
The interrupt request from a logical device or
IRQIN may be output on the IRQH signal.
Refer to the configuration registers for more
information.
OD24
If EPP or ECP Mode is enabled, this output is
pulsed low, then released to allow sharing of
interrupts.
12
SMSC [ SMSC CORPORATION ]
