Parallel Interface Programming - HP Compaq d330 DT Technical Reference Manual

5.5.4 PARALLEL INTERFACE PROGRAMMING

Programming the parallel interface consists of configuration, which typically occurs during POST,
and control, which occurs during runtime.
5.5.4.1 Parallel Interface Configuration
The parallel interface must be configured for a specific address range (LPT1, LPT2, etc.) and also
must be enabled before it can be used. When configured for EPP or ECP mode, additional
considerations must be taken into account. Address selection, enabling, and EPP/ECP mode
parameters of the parallel interface are affected through the PnP configuration registers of the
LPC47B387 I/O controller. Address selection and enabling are automatically done by the BIOS
during POST but can also be accomplished with the Setup utility and other software.
The parallel interface configuration registers are listed in the following table:
Table 5-13. Parallel Interface Configuration Registers
Parallel Interface Configuration Registers
Index
Address Function
30h Activate
60h Base Address MSB
61h Base Address LSB
70h Interrupt Select
74h DMA Channel Select
F0h Mode Register
F1h Mode Register 2
Table 5-13.
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
hp compaq d330 and d530 Series of Personal Computers
Featuring the Intel Pentium 4 Processor
First Edition – June 2003
Technical Reference Guide
Reset
Value
00h
00h
00h
00h
04h
00h
00h
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