Chapter 4 System Support

4.8.2 LPC47B367 I/O CONTROLLER FUNCTIONS

The LPC47B367 I/O controller contains various functions such as the keyboard/mouse interfaces, diskette interface, serial interfaces, and parallel interface. While the control of these interfaces uses standard AT-type I/O addressing (as described in chapter 5) the configuration of these functions uses indexed ports unique to the LPC47B367. In these systems, hardware strapping selects I/O addresses 02Eh and 02Fh at reset as the Index/Data ports for accessing the logical devices within the LPC47B367. Table 4-18 lists the PnP standard control registers for the LPC47B367.

Table 4-18LPC47B367 I/O Controller Registers

Table 4-18.

LPC47B367 I/O Controller Control Registers

Index

Function

Reset Value

02h

Configuration Control

00h

03h

Reserved

 

07h

Logical Device (Interface) Select:

00h

 

00h

= Diskette Drive I/F

 

 

01h

= Reserved

 

 

02h

= Reserved

 

 

03h

= Parallel I/F

 

 

04h

= Serial I/F (UART 1/Port A)

 

 

05h

= Serial I/F (UART 2/Port B)

 

 

06h

= Reserved

 

 

07h

= Keyboard I/F

 

 

08h

= Reserved

 

 

09h

= Reserved

 

 

0Ah = Runtime Registers (GPIO Config.)

 

 

0Bh = SMBus Configuration

 

20h

Super I/O ID Register (SID)

56h

21h

Revision

--

22h

Logical Device Power Control

00h

23h

Logical Device Power Management

00h

24h

PLL / Oscillator Control

04h

25h

Reserved

 

26h

Configuration Address (Low Byte)

 

27h

Configuration Address (High Byte)

 

28-2Fh

Reserved

 

NOTE:

For a detailed description of registers refer to appropriate SMC documentation.

The configuration registers are accessed through I/O registers 2Eh (index) and 2Fh (data) after the configuration phase has been activated by writing 55h to I/O port 2Eh. The desired interface (logical device) is initiated by firmware selecting logical device number of the 47B347 using the following sequence:

1.Write 07h to I/O register 2Eh.

2.Write value of logical device to I/O register 2Fh.

3.Write 30h to I/O register 2Eh.

4.Write 01h to I/O register 2Fh (this activates the interface).

Writing AAh to 2Eh deactivates the configuration phase.

4-32Compaq Evo and Workstation Personal Computers

Featuring the Intel Pentium 4 Processor

Second Edition – January 2003

Page 86
Image 86
Compaq W4000 2 LPC47B367 I/O Controller Functions, LPC47B367 I/O Controller Control Registers, Index Function Reset Value