Chapter 4 System Support
Compaq Deskpro EX Series of Personal Computers
First Edition - August 2000
4-40
4.9.3 LPC47B357 I/O CONTROLLER FUNCTIONS
The LPC47B357 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 LPC47B357. 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 LPC47B357.
Table 4-19 lists the PnP standard control registers for the LPC47B357.
Table 4-19
LPC47B357 Control Registers
Table 4-19.
LPC47B357 I/O Controller Control Registers
Index
Function
Reset Value
02h
Configuration Control
00h
03h
Reserved
07h
Logical Device (Interface) Select:
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 = Reserved
00h
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 47B357 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.
Содержание Deskpro EX
Страница 2: ......
Страница 4: ......
Страница 6: ......
Страница 8: ...Technical Reference Guide Compaq Deskpro EX Series of Personal Computers First Edition August 2000 ii ...
Страница 180: ...Appendix A Error Messages and Codes Compaq Personal Computers Changed June 2000 A 12 This page is intentionally blank ...
Страница 214: ...This page is intentionally blank ...