国产精品成人VA在线观看-国产乱妇乱子视频在播放-国产日韩精品一区二区三区在线-国模精品一区二区三区

參數資料
型號: W83787IF
廠商: WINBOND ELECTRONICS CORP
元件分類: 外設及接口
英文描述: WINBOND I/O WITH SERIAL-INFRARED SUPPORT
中文描述: MULTIFUNCTION PERIPHERAL, PQFP100
封裝: PLASTIC, QFP-100
文件頁數: 72/123頁
文件大小: 1751K
代理商: W83787IF
W83787IF
Publication ReleaseDate:Sep 1995
- 72 -
Revision A1
Once this bit is set high, the FDC operates normally, but because pin WE
is inactive, the FDD will not
write data to diskettes. For example, if a diskette is formatted with DISFDDWR = 1, after the format
command has been executed, messages will be displayed that appear to indicate that the format is
complete. If the diskette is removed from the disk drive and inserted again, however, typing the DIR
command will reveal that the contents of the diskette have not been modified and the diskette was
not actually reformatted.
The reason for this is that as the operating system (e.g., DOS) reads the diskette files, it keeps the
files in memory. If there is a write operation, DOS will write data to the diskette and memory
simultaneously. When DOS wants to read the diskette, it will first search the files in memory. If DOS
finds the file in memory, it will not issue a read command to read the diskette. When DISFDDWR = 1,
DOS still writes data to the diskette and memory, but only the data in memory are updated. If a read
operation is performed, data are read from memory first, and not from the diskette. The action of
removing the diskette from the drive and inserting it again forces the DSKCHG pin active. DOS will
then read the contents of the diskette and will show that the contents have not been modified. The
same holds true with write commands.
The disable FDD write function allows users to protect diskettes against computer viruses by ensuring
that no data are written to the diskette.
SWWP (Bit 4):
0
1
Normal, use
WP
to determine whether the FDD is write-protected or not
FDD is always write-protected
Media ID 1 Media ID 0 (Bit 3, 2):
These two bits hold the media ID bit 1, 0 for three mode
Floppy Boot Drive 1 Floppy Boot Drive 0 (bit 1, 0)
These two bits hold the value of floppy boot drive 1 and drive 0 for three mode
相關PDF資料
PDF描述
W83787F WINBOND I/O WITH SERIAL-INFRARED SUPPORT
W83791D W83791D Winbond H/W Monitoring IC
W83791SD H/W MONITORING IC
W83791SG H/W MONITORING IC
W83877AF Multi-Function I/O Port Controller(多功能輸入/輸出口控制器)
相關代理商/技術參數
參數描述
W83791D 制造商:WINBOND 制造商全稱:Winbond 功能描述:Winbond H/W Monitoring IC
W83791G 功能描述:IC MONITOR H/W 48-LQFP RoHS:是 類別:集成電路 (IC) >> PMIC - 熱管理 系列:- 標準包裝:1 系列:- 功能:溫度監控系統(傳感器) 傳感器類型:內部和外部 感應溫度:-40°C ~ 125°C,外部傳感器 精確度:±2.5°C 本地(最大值),±5°C 遠程(最大值) 拓撲:ADC,比較器,寄存器庫 輸出類型:2 線 SMBus? 輸出警報:無 輸出風扇:無 電源電壓:2.7 V ~ 5.5 V 工作溫度:-40°C ~ 125°C 安裝類型:表面貼裝 封裝/外殼:SOT-23-8 供應商設備封裝:SOT-23-8 包裝:Digi-Reel® 其它名稱:296-22675-6
W83791SD 制造商:WINBOND 制造商全稱:Winbond 功能描述:H/W MONITORING IC
W83791SG 制造商:WINBOND 制造商全稱:Winbond 功能描述:H/W MONITORING IC
W83792AD 制造商:WINBOND 制造商全稱:Winbond 功能描述:H/W Monitoring IC (CSB Version)