LPC47M172 SMSC Corporation, LPC47M172 Datasheet - Page 93

• Manufacturer Part Number: LPC47M172
• Description: ADVANCED I/O CONTROLLER WITH MOTHERBOARD GLUE LOGIC
• Manufacturer: SMSC Corporation

BITS 1, 2
BIT 3 nERR – nERROR
BIT 4 SLT - PRINTER SELECTED STATUS
BIT 5 PE - PAPER END
BIT 6 nACK - ACKNOWLEDGE
BIT 7 nBUSY - nBUSY
7.4.3
BIT 0 STROBE - STROBE
BIT 1 AUTOFD - AUTOFEED
BIT 2 nINIT - INITIATE OUTPUT
BIT 3 SLCTIN - PRINTER SELECT INPUT
SMSC LPC47M172
Parallel Port Mode Register 2, 0xF1 in Serial Port Logical Device Configuration Registers) is ‘1’, the
TMOUT bit is cleared on the trailing edge of a read of the EPP Status Register.
Are not implemented as register bits, during a read of the Printer Status Register these bits are a low level.
The level on the nERROR input is read by the CPU as bit 3 of the Printer Status Register. A logic 0
means an error has been detected; a logic 1 means no error has been detected.
The level on the SLCT input is read by the CPU as bit 4 of the Printer Status Register. A logic 1 means
the printer is on line; a logic 0 means it is not selected.
The level on the PE input is read by the CPU as bit 5 of the Printer Status Register. A logic 1 indicates a
paper end; a logic 0 indicates the presence of paper.
The level on the nACK input is read by the CPU as bit 6 of the Printer Status Register. A logic 0 means
that the printer has received a character and can now accept another. A logic 1 means that it is still
processing the last character or has not received the data.
The complement of the level on the BUSY input is read by the CPU as bit 7 of the Printer Status Register.
A logic 0 in this bit means that the printer is busy and cannot accept a new character. A logic 1 means that
it is ready to accept the next character.
Control Port
ADDRESS OFFSET = 02H
The Control Port is located at an offset of ‘02H’ from the base address. The Control Register is initialized
by the RESET input, bits 0 to 5 only being affected; bits 6 and 7 are hard wired low.
This bit is inverted and output onto the nSTROBE output.
This bit is inverted and output onto the nAutoFd output. A logic 1 causes the printer to generate a line feed
after each line is printed. A logic 0 means no autofeed.
This bit is output onto the nINITP output without inversion.
This bit is inverted and output onto the nSLCTIN output. A logic 1 on this bit selects the printer; a logic 0
means the printer is not selected.
DATASHEET
Page 93
Advanced I/O Controller with Motherboard GLUE Logic
SMSC/Non-SMSC Register Sets (Rev. 02-27-04)
Datasheet