Specifications

Software Configuration
3–25
Register Bit Definitions:
Signal
Name Full Name Description
TMOUT Timeout Valid only in EPP mode , this signal goes true
after a 10 uS time-out has occurred on the
EPP bus. This bit is cleared by reset.
-ERR Error Reflects the status of the -ERROR input. 0
means an error has occurred.
SLCT Printer selected
status
Reflects the status of the SLCT input. 1
means a printer is on-line.
PE Paper end Reflects the status of the PE input. 1 indicates
paper end.
-ACK Acknowledge Reflects the status of the ACK input. 0
indicates a printer received a character..
-BUSY Busy Reflects the complement of the BUSY input. 0
indicates a printer is busy.
STROBE Strobe This bit is inverted and output to the -STROBE
pin.
AUTOFD Auto feed This bit is inverted and output to the -AUTOFD
pin.
-INIT Initiate output This bit is output to the -INIT pin.
SLC Printer select
input
This bit is inverted and output to the pin. It
selects a printer.
IRQE Interrupt request
enable
When set to 1, interrupts are enabled. An
interrupt is generated by the positive-going -
ACK input.
PCD Parallel control
direction
When set to 1, port is in input mode. In printer
mode, the printer is always in output mode
regardless of the state of this bit.
PD0-PD7 Parallel Data Bits
Table 3-10 Standard and PS/2 Mode Register Bit Definitions
3.10.2 EPP and ECP Operation
The board’s parallel port is compliant with the IEEE 1284 Extended Capabilities Port Protocol and ISA
Standard (Rev 1.09, January 7, 1993), developed by Microsoft. Contact IEEE Customer Service and
request IEEE Std 1284 for information about EPP and ECP operation.