Compaq W4000 Manual De Usuario

Technical Reference Guide 

 

 

Programming the parallel interface consists of configuration, which typically occurs during POST, 
and control, which occurs during runtime. 

 

 
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 
LPC47B357 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 5–10.   Parallel Interface Configuration Registers 
 

 

 

 

      

       Parallel Interface Configuration Registers 

30h Activate 

R/W 

00h 

60h 

Base Address MSB 

R/W 

00h 

61h 

Base Address LSB 

R/W 

00h 

70h Interrupt 

Select 

R/W 

00h 

74h 

DMA Channel Select 

R/W 

04h 

F0h Mode 

Register 

R/W 

00h 

F1h 

Mode Register 2 

R/W 

00h 

 
 
 
 
 
 

 

5-13