參數(shù)資料
型號: VT8231
廠商: Electronic Theatre Controls, Inc.
元件分類: 晶體
英文描述: CRYSTAL 8.00MHZ 18PF SMD
中文描述: 南橋伏特,PC99柔順
文件頁數(shù): 68/132頁
文件大?。?/td> 1210K
代理商: VT8231
VT8231
Preliminary Revision 0.8
October 29, 1999
-
62-
Function 0 Registers - PCI to ISA Bridge
7HFKQRORJLHV,QF
:H &RQQHFW
Offset 59
PCS0# Control ............................................... RW
7-4
Reserved
........................................ always reads 0
3
PCS0# Pin Function (Pin T5)
0
Pin is defined as PCS0# ........................default
1
Pin is defined as Internal Trap I/O
2-0
Reserved
........................................ always reads 0
Offset 5A
KBC / RTC Control ...................................... RW
Bits 7-4 of this register are latched from pins SD7-4 at power-
up but are read/write accessible so may be changed after
power-up to change the default strap setting:
7
6
5
4
3
Keyboard RP16
............................. latched from SD7
Keyboard RP15
............................ latched from SD6
Keyboard RP14
............................ latched from SD5
Keyboard RP13
............................ latched from SD4
Audio Function Enable
....... RO, strapped from SPKR pin V5
0
Disable (SDD pins function as SDD)
1
Enable (SDD pins function as Audio / Game)
Internal RTC Enable
0
Disable
1
Enable ....................................................default
Internal PS2 Mouse Enable
0
Disable ..................................................default
1
Enable
Internal KBC Enable
0
Disable ..................................................default
1
Enable
2
1
0
Note:
External strap option values may be set by connecting
the indicated external pin to a 4.7K ohm pullup (for
1) or driving it low during reset with a 7407 TTL
open collector buffer (for 0) as shown in the
suggested circuit below:
9&&
.
6'Q
5(6(7
9&&
Figure 5. Strap Option Circuit
Offset 5B - Internal RTC Test Mode .............................. RW
7-4
Reserved
........................................always reads 0
3
Map RTC Rx32 to Rx3F
0
Disable...................................................default
1
Enable
2
RTC Reset Enable
(do not program)
0
Disable...................................................default
1
Enable
1
RTC SRAM Access Enable
0
Disable...................................................default
1
Enable
This bit is set if the internal RTC is disabled but it is
desired to still be able to access the internal RTC
SRAM via ports 74-75. If the internal RTC is
enabled, setting this bit does nothing (the internal
RTC SRAM should be accessed at either ports 70/71
or 72/73.
0
RTC Test Mode Enable
(do not program) .default=0
Offset 5C - DMA Control ................................................ RW
7
PCS0# & PCS1# 16-Bit I/O
0
Disable...................................................default
1
Enable
6
Passive Release
0
Disable...................................................default
1
Enable
5
Internal Passive Release
0
Disable...................................................default
1
Enable
4
Dummy PREQ
0
Disable...................................................default
1
Enable
3
Reserved
........................................always reads 0
2
APIC Connection
0
APIC on SD Bus....................................default
1
APIC on XD Bus
1
Reserved (Do Not Program)
....................default = 0
0
DMA Line Buffer Disable
0
DMA cycles can be to/from line buffer .......def
1
Disable DMA Line Buffer
相關(guān)PDF資料
PDF描述
VT82885(24DIP) Real-Time Clock
VT82885(28PLCC) Real-Time Clock
VT82887 Real-Time Clock
VT82885 Real Time Clock
VT82C42 VT82C42 Keyboard Controller
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
VT82885 制造商:未知廠家 制造商全稱:未知廠家 功能描述:electrical characteristics, bus timing and pin descriptions follows.
VT82885(24DIP) 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Real-Time Clock
VT82885(28PLCC) 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Real-Time Clock
VT82887 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Real Time Clock
VT82A192 制造商:未知廠家 制造商全稱:未知廠家 功能描述: