NCT6627UD Nuvoton Technology Corporation of America, NCT6627UD Datasheet - Page 135

• Manufacturer Part Number: NCT6627UD
• Manufacturer: Nuvoton Technology Corporation of America

Specifications of NCT6627UD

• Lead Free Status / Rohs Status: Supplier Unconfirmed

The CPU reads the contents of the printer control latch by reading the printer control swapper. The bit definitions
are as follows:
The address port is available only in EPP mode. Bit definitions are as follows:
The contents of DB0-DB7 are buffered (non-inverting) and output to ports PD0-PD7 during a write operation. The
leading edge of IOW# causes an EPP address write cycle to be performed, and the trailing edge of IOW# latches
the data for the duration of the EPP write cycle.
PD0-PD7 ports are read during a read operation. The leading edge of IOR# causes an EPP address read cycle to
be performed and the data to be output to the host CPU.
DEFAULT
NAME
BIT
BIT
7-6
NAME
11.2.3
11.2.4
11.2.5
2
1
0
BIT
5
4
3
2
1
0
BIT
1
1
TMOUT. This bit is only valid in EPP mode. A logical 1 indicates that a 10-μs time-out has
occurred on the EPP bus; a logical 0 means hat no time-out error has occurred. Writing a
logical 1 to this bit clears the time-out status bit; writing a logical 0 has no effect.
These two bits are always read as logical 1 and can be written.
DIR (Direction Control Bit). When this bit is logical 1, the parallel port is in the input mode
(read). When it is logical 0, the parallel port is in the output mode (write). This bit can be
read and written. In SPP mode, this bit is invalid and fixed at zero.
IRQ ENABLE. A logical 1 allows an interrupt to occur when ACK# changes from low to
high.
SLCT IN. a logical 1 selects the printer.
INIT#. A logical 0 starts the printer (50 microsecond pulse, minimum).
AUTO FD. A logical 1 causes the printer to line-feed after a line is printed.
STROBE. A logical 1 generates an active-high pulse for a minimum of 0.5 μs to clock
data into the printer. Valid data must be presented for a minimum of 0.5 μs before and
after the strobe pulse.
Printer Control Latch and Printer Control Swapper
EPP Address Port
EPP Data Port 0-3
7
1
PD7
7
6
1
PD6
6
DIR
NA
5
PD5
5
IRQ ENABLE
DESCRIPTION
DESCRIPTION
4
0
PD4
4
SLCT IN
-126-
NA
PD3
3
3
W83627UHG/NCT6627UD
INIT#
NA
PD2
Publication Release Date: October 26, 2010
2
2
AUTO FD
PD1
NA
1
1
STROBE
PD0
NA
0
0
Revision 1.7